GPS World

Tag: NSRS

  • Plate tectonics and NGS’s new NSRS terrestrial reference frames

    Plate tectonics and NGS’s new NSRS terrestrial reference frames

    The adoption of the new, modernized National Spatial Reference System (NSRS) is rapidly approaching, with official implementation now expected in the first quarter of 2027.

    One of the most common questions I receive during presentations is: How will the National Geodetic Survey (NGS) account for plate tectonics in the modernized NSRS, and what does that mean for my geospatial products and services?

    First, I have some very sad news to share.

    Dr. Chris Pearson
    Dr. Chris Pearson

    Our friend and colleague, Dr. Chris Pearson, unexpectedly passed away while in Cape Town attending the May 2026 International Federation of Surveyors (FIG) conference. At the time, he was serving as a Geodetic Advisor for Trimble and as co-chair of FIG Commission 5.2.

    Chris previously worked for the National Geodetic Survey (NGS) as a Geodetic Advisor, where he played a key role in developing the comprehensive block model of crustal deformation — widely known as HTDP — across the western United States, including Alaska.

    He was an active and respected member of several professional organizations and will be greatly missed by the entire geodetic and surveying community.

    Now, let’s discuss how the National Geodetic Survey (NGS) will handle plate tectonics in the modernized National Spatial Reference System (NSRS) and what this will mean for users’ geospatial products and services.

    Map of tectonic plates (Image: Dave Zilkoski)

    Plate tectonics is the scientific theory that describes how Earth’s outer shell, known as the lithosphere, is divided into large, rigid pieces called tectonic plates. These plates float atop the hotter, more ductile rock in the mantle below and move very slowly — roughly at the same rate as your fingernails grow, about 1 to 10 centimeters per year.

    So why does plate tectonics matter for geodetic coordinates? Because the most significant geological activity — including earthquakes, volcanic eruptions, and crustal deformation — occurs primarily at the boundaries where these plates interact.

    My last newsletter highlighted several activities by the North Carolina 2022 Reference Frame Working Group (NC RFWG) that are addressing this issue and other challenges related to the implementation of the new NSRS.

    During my presentations on the modernized NSRS, I always show the National Geodetic Survey (NGS) maps that illustrate the approximate horizontal and vertical changes expected when the new Terrestrial Reference Frames (TRFs) are adopted, with coordinates referenced to epoch 2020.00. These maps provide a high-level (“30,000-foot”) overview of the anticipated changes. However, they do not include the level of detail that many users are looking for.

    Participants at these seminars and meetings consistently want to know the expected coordinate differences for their specific state or local region, and how the time-dependent components will impact their work.

    Most geospatial users now understand that International Terrestrial Reference Frame (ITRF) coordinates include a velocity component caused by tectonic plate movement. To manage these changing coordinates, the National Geodetic Survey (NGS) plans to incorporate time-dependent modeling. NGS has developed two key models — EPP2022 and IFDM2022 — to make time-dependent geodetic control practical and usable.

    • EPP2022 (Euler Pole Parameters) describes the rigid rotation of tectonic plates.
    • IFDM2022 (Intra-Frame Deformation Model) computes the internal deformation and drift within a tectonic plate.

    As shown in the figure below, the NOAA CORS Network station COLA in Columbia, South Carolina — located on the North American Plate — is moving at approximately 0.05 feet (14 mm) per year.

    This velocity is provided on the published ITRF2020 position and velocity data for the station  (NGS CORS Position and Velocity Sheet for COLA).  As a result, a surveyor working in June 2026 would observe a shift of about 0.3 feet in the ITRF2020 horizontal coordinates compared to the 2020.00 reference epoch, solely due to tectonic plate motion.

    Motion due to plate movement (rates per year) – based on ITRF2020 velocity rates

    Image: Dave Zilkoski
    (Image: Dave Zilkoski)

    The National Geodetic Survey (NGS) provides detailed information for all NOAA CORS Network (NCN) stations on the NGS NCN Station Pages. 

    In the section titled “Coordinates and Velocities”, simply click the Position and Velocity button to view the station’s ITRF2020 coordinates and velocities (referenced to epoch 2020.00), as well as the NAD 83 (2011) coordinates and velocities (referenced to epoch 2010.00).

    NGS CORS position and velocity sheet for COLA

    NGS CORS position and velocity sheet for COLA

    So, what does this mean for users?

    As previously mentioned, the National Geodetic Survey (NGS) is expected to adopt the new modernized NSRS in the first quarter of 2027. The figure below shows the change in ITRF2020 coordinate values between epoch 2020.00 and 2027.00 for NOAA CORS Network (NCN) stations in South Carolina. This shift of approximately 0.33 feet (10 cm) is the result of seven years of tectonic plate motion.

    ITRF2020, Epoch 2020 to ITRF2020, Epoch 2027 (units ift)

    ITRF2020, Epoch 2020 to ITRF2020, Epoch 2027 (units ift) Image: Dave Zilkoski
    Image: Dave Zilkoski

    That said, what will the change in NATRF2022 coordinate values be between epoch 2020.00 and 2027.00?

    This is where NGS’s EPP2022 and IFDM2022 models become essential. My February 2022 and July 2024 GPS World newsletters discussed the Euler Pole Parameters (EPP) process in detail.

    The Beta NATRF2022 website provides the Euler Pole Parameters (EPP) needed to define the relationship between ITRF2020 and the new NATRF2022 frames for the North American, Caribbean, Pacific, and Mariana plates, as outlined in NGS’s Blueprint Part 1 document. The values in the table have proven especially useful to programmers developing and testing their software.

    Beta Values for EPP

    Beta Values for EPP (Image: NGS)
    (Image: NGS)

    As stated in Blueprint Part 1, the National Geodetic Survey (NGS) will define the official relationship between ITRF2020 and the four NSRS Terrestrial Reference Frames (TRFs) through Equation 59. This equation uses the rotation matrix provided in Equation 58, which results in Equation 60.

    See the box titled “Official Relationship Between ITRF2020 and the Four NSRS TRFs” for the equations.

    Official relationship between ITRF2020 and the four NSRS TRFs

    Official relationship between ITRF2020 and the four NSRS TRFs (Image: NGS Blueprint pt. 1)
    (Image: NGS Blueprint pt. 1)

    So, what does this mean for surveyors?

    The primary purpose of the EPP2022 model is to remove the rigid tectonic plate motion from the coordinates. After applying the EPP2022 model to the ITRF2020 coordinates at epoch 2027.00, the resulting NATRF2022 horizontal coordinates for station COLA (epoch 2027.00) will change by only 0.04 feet (12 mm).

    EPP applied

    NATRF2022, Epoch 2020 to NATRF2022, Epoch 2027 in SC (units ift)

    Image: Dave Zilkoski
    Image: Dave Zilkoski

    As shown in the figure, the EPP2022 model removes most of the horizontal movement caused by seven years of tectonic plate motion — reducing it to just 0.04 feet (1.2 cm) at station COLA. In other words, the EPP model effectively removes the vast majority of plate tectonic effects.

    Additionally, the plot shows that the relative horizontal differences between nearby marks are very small — typically less than 0.01 feet (0.3 cm).

    As previously mentioned, the NGS maps provide a high-level (“30,000-foot”) view of the expected changes between the current NSRS and the new modernized NSRS. So, what are the anticipated differences between NAD 83 (2011) and NATRF2022 specifically in South Carolina?

    The figures below illustrate the differences in both horizontal position and ellipsoid heights between NAD 83 (2011) and NATRF2022 coordinates across South Carolina.

    NAD83 (2011), Epoch 2010 to NATRF2022, Epoch 2020 Horizontal Changes in SC (Units ift)

    NAD83 (2011), Epoch 2010 to NATRF2022, Epoch 2020 Ellipsoid Height Changes in SC (Units ift)

    The magnitude of these changes varies depending on your location. To illustrate this, I’ve provided two additional examples: one for Iowa and one for Washington State. As the plots clearly show, the differences in these states are noticeably different from those depicted for South Carolina.

    NAD83 (2011), Epoch 2010 to NATRF2022, Epoch 2020 Horizontal Changes (Units ift)

    That said, the differences between NATRF2022 at epoch 2020.00 and epoch 2027.00 in Iowa and Washington State — after applying the EPP2022 model — are very similar to the values shown for South Carolina.

    However, readers should note that the differences in Washington State increase as you move toward the coast. This is because the area lies near the boundary between the North American Plate and the Pacific Plate. The Juan de Fuca Plate, a small microplate in the eastern North Pacific, is also actively involved in this region.

    (See the box titled “Juan de Fuca Plate.”)

    NATRF2022, Epoch 2020 to NATRF2022, Epoch 2027 (units ift)EPP Applied

    Juan de Fuca Plate

    The Juan de Fuca plate or Juan de Fuca microplate is a small oceanic tectonic plate (microplate) generated from the Juan de Fuca Ridge that is subducting beneath the northerly portion of the western side of the North American plate at the Cascadia subduction zone.

    Image: Dave Zilkoski
    Image: Dave Zilkoski

    What about orthometric height changes in the new NSRS?

    As an example, the orthometric height differences between NAPGD 2022 and NAVD 88 in South Carolina are expected to range from approximately -0.8 feet to -1.3 feet.

    Difference between NAPGD2022 and NAVD 88 (Units ift) in S.C.

    Image: Dave Zilkoski
    Image: Dave Zilkoski

    The differences between NAPGD 2022 and NAVD 88 vary significantly depending on your location. The figures below illustrate these orthometric height differences for Iowa and Washington State as examples.

    Difference between NAPGD2022 and NAVD 88 (Units ift)

    The new NSRS will use a gravimetric geoid (GEOID2022) rather than a hybrid geoid (GEOID18) to compute GNSS-derived orthometric heights.

    During my presentations, I always remind participants that a hybrid geoid is not a “true” geoid. It is simply a transformation model that converts ellipsoid heights in one reference frame to orthometric heights in a specific vertical datum. Specifically, GEOID18 is a transformation tool that allows users to derive NAVD 88 orthometric heights from NAD 83 (2011), epoch 2010 ellipsoid heights.

    The figure below shows the differences between the gravimetric geoid model GEOID2022 and the hybrid geoid model GEOID18.

    Important note: Users cannot use GEOID18 with NATRF2022 ellipsoid heights to obtain NAVD 88 orthometric heights. Instead, GEOID2022 must be used with NATRF2022 ellipsoid heights to compute orthometric heights in the new vertical datum, NAPGD 2022.

    Differences between GEOID2022 and GEOID18 in SC (Units ift)

    As noted at the outset of this newsletter, the transition to the modernized National Spatial Reference System (NSRS) is rapidly approaching, with official implementation scheduled for the first quarter of 2027.

    The National Geodetic Survey (NGS) released the following announcement on May 28, 2026:

    Public Testing Period Ends for Key NSRS Modernization Products

    NGS has declared the following products stable and ready for implementation planning and integration activities ahead of the official release:

    • North American-Pacific Geopotential Datum of 2022 (NAPGD2022)
    • New Terrestrial Reference Frames of 2022:
      • North America (NATRF2022)
      • Pacific (PATRF2022)
      • Caribbean (CATRF2022)
      • Mariana (MATRF2022)
    • State Plane Coordinate System of 2022 (SPCS2022)

    Additional modernization products, including NCAT, OPUS, and the Data Delivery System, are scheduled for release later in 2026.

    NGS news

    Public testing period ends on specific NSRS modernization products

    Image: NOAA

    Image: NOAA

    This newsletter highlighted the role of the EPP2022 model in accounting for plate tectonics and illustrated the anticipated local differences between the current National Spatial Reference System (NSRS) and the upcoming modernized version.

    Future editions will continue to explore additional NGS Beta products as they are released later in 2026.

  • Update on NC 2022 reference frame working group: Preparing information for NC geospatial providers and users

    Update on NC 2022 reference frame working group: Preparing information for NC geospatial providers and users

    In my October 2025 GPS World Newsletter, I highlighted professional societies forming working groups for the new NSRS — the National Society of Surveyors (NSPS), the American Society of Photogrammetry and Remote Sensing (ASPRS), and the American Association for Geodetic Surveyor (AAGS). Under Gary Thompson’s leadership, the North Carolina Geodetic Survey also established the North Carolina 2022 Reference Frame Working Group (NC RFWG), which includes representatives from NC agencies that produce or use geospatial products and services. This newsletter spotlights several NC RFWG activities to inform and assist other agencies and working groups.

    As noted in my previous newsletter, NC RFWG agencies are proactively conducting self-assessments of their needs and processes to identify challenges and opportunities early, enabling a smooth transition and sustained operational efficiency. The working group meets monthly to review progress on activities.

    One key task of the working group was to develop a short online questionnaire. The goal was to open a dialogue with geospatial professionals and better understand their readiness for the upcoming modernization of the National Spatial Reference System (NSRS).

    The questionnaire was designed to address the following key questions:

    • Are you prepared to implement the new NSRS once the National Geodetic Survey (NGS) officially adopts it?
    • Do you have the necessary tools and resources in place to ensure a smooth transition?
    • Has your organization established a timeline for transitioning to the modernized NSRS?
    • What concerns do you have regarding the transition to the new NSRS?

    The section titled “Introduction of North Carolina Questionnaire” explains the purpose and background of the survey, while the section titled “North Carolina Online Questions” presents the list of questions included in the questionnaire.

    Introduction of the North Carolina Questionnaire

    This questionnaire seeks stakeholder input on the upcoming modernization of the National Spatial Reference System (NSRS). Your feedback is welcome on the proposed questions, as well as any concerns about the datum transition, tools (such as updated NCAT, OPUS, and SPCS2022), data transformation strategies, workflow impacts, and preparation needs.

    The National Geodetic Survey (NGS) is replacing the North American Datum of 1983 and the North American Vertical Datum of 1988 with new plate-fixed terrestrial reference frames (NATRF2022, PATRF2022, CATRF2022, and MATRF2022) tied to the International Terrestrial Reference Frame 2020, along with the new vertical datum, the North American-Pacific Geopotential Datum of 2022.

    In spring 2027, new horizontal and vertical datums will be implemented:

    Horizontal

    • North American Terrestrial Reference Frame (NATRF2022)
    • Replaces the North American Datum of 1983 (2011)

    Vertical

    • North American-Pacific Geopotential Datum of 2022 (NAPGD2022)
    • Replaces North American Vertical Datum of 1988

    Units

    • 14B NCAC 03 .0602 REQUIRED FOOT CONVERSION

    North Carolina Online Questions

    The section titled “Results of North Carolina Online Questionnaire” summarizes the survey responses collected as of April 27, 2026.

    [Note: NCPMA refers to the North Carolina Property Mappers Association, and LGUC refers to the North Carolina Local Government Committee.]

    Results of the North Carolina Online Questionnaire

    (April 27, 2026)

    This questionnaire solicited input from the North Carolina Property Mappers Association (NC PMA), the North Carolina Geographic Information Coordinating Council (GICC), and the North Carolina Local Government Committee (LGC). Although focused on North Carolina, the results may benefit other working groups. The NC working group is reviewing all feedback—especially regarding the Spring 2027 datum change—and will develop materials to address it.

    In addition to the questionnaire, the working group prepared a short guidance document on the new reference frames for local governments and state agencies. It outlines how to prepare for the 2027 datum change and covers:

    • Preliminary steps for transitioning when NGS and North Carolina officially adopt the new datums in 2027.
    • Actions users can take now to ready NSRS‑referenced data for the modernized NSRS and the shift from U.S. Survey Foot/International Foot.
    • Estimated coordinate changes with the 2027 adoption of:
      • North American Terrestrial Reference Frame (NATRF2022)
      • North American-Pacific Geopotential Datum of 2022 (NAPGD2022)
      • New national geoid model (Geoid2022)
      • North Carolina State Plane Coordinate System of 2022 (SPCS2022)
    • Current NC statewide digital orthoimagery acquisition cycle and statewide lidar collection schedule.
    • How the NC CORS and Real-Time Network (RTN) will support the modernized NSRS.
    • Web links to more detailed resources.


    The working group is developing a case study on preparing a FEMA Elevation Certificate using the modernized NSRS (NATRF2022 and NAPGD2022). It will be featured in upcoming newsletters. The North Carolina Geodetic Survey will host the materials on its website, and I’ll share the public link once it’s available.

  • NGS presents the latest NSRS news at Geo Week 2026

    NGS presents the latest NSRS news at Geo Week 2026

    In my January 2026 GPS World newsletter, I noted that the National Geodetic Survey (NGS) convened the Federal Geodetic Control Subcommittee (FGCS) meeting with federal geospatial agencies to boost awareness and align efforts on National Spatial Reference System (NSRS) Modernization government-wide. Key steps include cultivating internal champions to champion the initiative, distilling complex topics for clear leadership briefings, and bringing together agencies, partners, and industry to collaboratively shape solutions. I also highlighted that on Feb. 17-18, NGS staff would be participating in Geo Week 2026 in Denver to engage geospatial product and service users and further coordinate on the modernization. NGS gave several presentations during GeoWeek that addressed many of my questions on the new modernized NSRS. This newsletter will highlight some of NGS’s presentations.

    First, a special shout-out to my dear friend and former colleague, Juliana Blackwell, retired Director of the National Geodetic Survey. NOAA’s Table Mountain Gravity Observatory in Boulder, Colorado — long known for its absolute gravity work — has been officially renamed the J. P. Blackwell Gravity Observatory. This well-earned tribute honors her outstanding dedication and visionary leadership at NGS. Congratulations, Juliana!

    J. P. Blackwell Gravity Observatory. (Photo: NGS)
    J. P. Blackwell Gravity Observatory. (Photo: NGS)
    J. P. Blackwell Gravity Observatory. (Photo: NGS)
    J. P. Blackwell Gravity Observatory. (Photo: NGS)
    J. P. Blackwell Gravity Observatory. (Photo: NGS)
    J. P. Blackwell Gravity Observatory. (Photo: NGS)

    NGS employees participated in the following sessions and meetings during GeoWeek 2026:

    • ASPRS NSRS Modernization Working Group Meeting
    • NSRS Modernization — The Latest Technical Updates
    • Preparing to Put the Modernized National Spatial Reference System into Practice
    • Roundtable — NSRS Modernization and Professional Societies

    As President of the American Association for Geodetic Surveying (AAGS), I participated in the session titled “Roundtable – NSRS Modernization and Professional Societies.” Dana J Caccamise II, NGS regional geodetic advisor, opened our session by describing the NGS Modernization Engagement Plan and Progress.  As I mentioned last month, Dana should get an award for the material he has prepared and for his work assisting agencies and professional organizations in preparing for the new NSRS. I highlighted Caccamise’s work in my October 2025 GPS World newsletter.

    All the NGS sessions provided the latest information on activities associated with NGS’s NSRS Modernization. Here are the specific questions I had going into the session, along with the clear answers provided by NGS personnel during their presentations and the follow-up Q&A:

    What NGS products and services will be available when federal agencies officially adopt the new NSRS?

    When the modernized NSRS is officially adopted (following FGCS approval and the transition to it becoming “the NSRS”), NGS will make available a full suite of updated tools, data access points, and services built around the new reference frames (e.g., NATRF2022 and variants), the North American-Pacific Geopotential Datum of 2022 (NAPGD2022), the State Plane Coordinate System of 2022 (SPCS2022), and associated geopotential models like GEOID2022. Key products expected to be operational and official include:

    • NCAT
    • NGS Maps
    • Geodetic Station Page
      • CORS
    • Geodetic Mark Page
      • Passive Marks
    • OPUS–Static 5.2
    • OPUS-Share

    What NGS products and services will NOT be available when federal agencies officially adopt the new NSRS?

    Upon official adoption of the modernized NSRS — after FGCS approval and the shift to the new system becoming “the NSRS” — several current products and services will no longer be part of the official modernized NSRS or will be discontinued in their present form. Key items not included or no longer supported in the modernized NSRS release include:

    • OPUS Projects 5 will not be supported
      • OPUS-Rapid Static (OPUS-RS) will not be supported (modernized OPUS-Static 5.2 is expected to handle a broader range of observations)
      • OPUS 6.0 and OPUS 6.1 will not be available

    What GNSS data will be included in the first iteration of the computation of Reference Epoch Coordinates (REC) for marks?

    At Geo Week 2026, NGS stated that its plans include providing Reference Epoch Coordinates (RECs) for certain legacy GNSS projects. Specifically, this includes:

    • GPS projects that were originally processed and published under the NAD 83 (2011) realization, and
    • Other GNSS projects will be officially published by NGS through the end of 2025\

    After the first iteration of Reference Epoch Coordinates, is NGS planning to perform future adjustments to determine REC and SEC of new marks? If so, what process will be used to establish RECs on new marks?

    Yes, NGS plans include performing future adjustments to compute Reference Epoch Coordinates (REC) for new marks. However, at this time, no final decision has been made on how often this will be performed.

    Has NGS changed how users need to submit data to incorporate leveling data into NAPDG2022?

    Yes, NGS has introduced changes to better integrate leveling data (differential height differences) into the modernized NSRS for computing orthometric Reference Epoch Coordinates (RECs) in NAPGD2022 (epoch 2020.00).

    As documented in Blueprint Document 3, when performing leveling projects, users will also be required to occupy a number of primary marks with GNSS.

    OPUS 6.1 is built for future expansion to support other geodetic measurements (classical, leveling)-no timeframe was given for this.

    Is NGS planning to officially adopt the new NSRS before users can submit data to NGS for technical review and publication in the NGS database?

    Yes, that is what NGS is saying at this moment (February 2026). OPUS Project 5 will not be supported and OPUS 6.1 will not be operational when the new NSRS is officially adopted.NGS is working on the OPUS 6 application and is trying to “minimize any gap in service.”

    Is NGS recommending using the OPUS-Share utility until users can submit data to NGS for technical review and publication in NGS database?

    Yes, that is what NGS is recommending at this moment (February 2026). 

    This is also stated in NGS’s Track Our Progress Webpage.

    OPUS-Projects 5 will not be included in the modernized NSRS. Instead, NGS will focus on both developing an improved software suite for OPUS, known as OPUS 6.0 and OPUS 6.1, and minimizing any gap in service in which the current OPUS-Projects functionality is not available for users to organize, process, adjust, and submit high-accuracy GPS surveys for use by NGS in expanding and improving the NSRS. As noted above, OPUS-Share will remain available as a means to submit data to NGS.

    When will OPUS 6.1 be available for users to submit data to NGS for technical review and publication in NGS database?  Is it weeks away, months away, or years away?

    NGS has not announced an official completion or release date for OPUS 6.0 and OPUS 6.1. However, they have indicated that active development is underway on this enhanced OPUS tool suite.  It’s not imminent— meaning not expected within several months—but it’s also not a distant, multi-year project.

    NGS is working on the application and is trying to “minimize any gap in service.”

    The NGS’s Track Our Progress Webpage states:

    “OPUS-Projects 5 will not be included in the modernized NSRS. Instead, NGS will focus on both developing an improved software suite for OPUS, known as OPUS 6, and minimizing any gap in service in which the current OPUS-Projects functionality is not available for users to organize, process, adjust, and submit high-accuracy GPS surveys for use by NGS in expanding and improving the NSRS. As noted above, OPUS-Share will remain available as a means to submit data to NGS.”

    What’s the cut-off date for users to submit projects via OPUS Project 5 so the data can be part of future computations of RECs?

    Current OPUS-Projects 5 is going to be supported until adoption of the new NSRS, with a deadline announced at least 6 months in advance.

    The NGS’s Track Our Progress Webpage states

    “Note: the current OPUS Projects 5 software will be supported until the modernized system is adopted, and a deadline for OPUS-Projects users to submit their surveys for publication will be announced with at least six months’ notice.”

    In the session “NSRS Modernization – The Latest Technical Updates,” the National Geodetic Survey (NGS) presented slides detailing the status and upcoming tasks for the modernized National Spatial Reference System (NSRS).  Key highlights from the presentation are summarized below.

    For the source of these slides and additional context, refer to the “Updates from the National Geodetic Survey at GeoWeek 2026” box.  NGS posts their presentations at here: https://geodesy.noaa.gov/web/science_edu/presentations_library/.

    Updates from the National Geodetic Survey at GeoWeek 2026

    (Selected Slides from the following presentations)

    • 2026 GeoWeek – NSRS Modernization – The Latest Technical Updates: The Why and How of NSRS mod – February 17, 2026 – Dru Smith
    • 2026 GeoWeek – Managing Modernization Rollout – February 17, 2026 – Seth Pollack
    • 106th Wyoming Engineering and Surveying (WES) Society Conference – February 5, 2026 – Brian Shaw
    • 2026 GeoWeek – Modernized Tools – February 17, 2026 – Brian Shaw

    2026 GeoWeek –   Updates to OPUS for Accessing the Modernized NSRS – February 17, 2026 – Dan Gillins

    During Dru Smith’s presentation, he mentioned what will be included in the first iteration of the computation of Reference Epoch Coordinates (REC) for marks. The slide states that more than 150,000 geometric (XYZ) coordinates and 1 million geopotential coordinates (that is, orthometric heights) will get reference epoch coordinates (REC), epoch 2020.00.  These will include data from NGS Integrated Database and from the OPUS Share database.

    First Reference Epoch Coordinates (REC). (Presented at GeoWeek 2026)
    First Reference Epoch Coordinates (REC). (Presented at GeoWeek 2026)
    First Reference Epoch Coordinates (REC). (Presented at 106th WES Society Conference)
    First Reference Epoch Coordinates (REC). (Presented at 106th WES Society Conference)

    In the GeoWeek 2026 presentation by Seth Pollack (from NOAA’s National Geodetic Survey), a slide outlined the NSRS modernization timeline.

    As detailed in the slide and consistent with NGS’s official rollout plan:

    • Beta products are currently being released incrementally on the beta site for public testing and feedback. This phased rollout began with initial beta releases in 2025 (following alpha in 2024) and continues through 2026, covering key components such as NAPGD2022, GEOID2022, SPCS2022, enhanced NCAT transformation tools, OPUS-Static updates, and forthcoming Data Delivery System features.
      • Each beta component, once released, undergoes public testing and stakeholder feedback, with overall testing continuing for at least 6 months after the final component is made available on the beta site.
    • Following sufficient testing—once all components appear stable and NGS has incorporated feedback—the Federal Geodetic Control Subcommittee (FGCS) will vote to recommend approval of the modernized NSRS. This vote is anticipated in late 2026 or early 2027.
    • Upon FGCS approval (and subsequent Federal Geographic Data Committee (FGDC) endorsement), NGS will probably publish a Federal Register Notice announcing the adoption.  At that point, the modernized NSRS becomes the official National Spatial Reference System, replacing the legacy system (NAD 83 realizations, NAVD 88, etc.).
      • While earlier NGS documentation targeted adoption likely in mid-to-late 2026 (post-FGCS vote), recent updates from GeoWeek 2026 sessions and related reports indicate the full official adoption and transition may extend into the first part of 2027, accounting for final testing, FGCS/FGDC processes, Federal Register steps, and a smooth handover to avoid disruptions.
    • The current NSRS remains official throughout this period. Users are encouraged to test beta products now and provide feedback to help refine the system.
    NSRS Modernization Timeline. (Presented at GeoWeek 2026)
    NSRS Modernization Timeline. (Presented at GeoWeek 2026)

    Brian Shaw, NGS’s expert on GIS products and services, presented key updates on how users will access geodetic data in the modernized National Spatial Reference System (NSRS).

    He emphasized the introduction of a revamped Data Delivery System (DDS), which includes:

    • Geodetic Mark Pages — for passive marks. These replace the current ASCII-text datasheets with modernized, user-friendly pages featuring updated Reference Epoch Coordinates (RECs), integrated photos, graphics, maps, project details, and easier navigation.
    • Geodetic Station Pages — for active stations like those in the NOAA CORS Network (NCN). These provide updated versions of existing CORS pages, including modernized coordinate functions (e.g., Coordinate Functions or time-dependent positioning info) aligned with the new reference frames (NATRF2022, etc.).
    • Additionally, Shaw highlighted a new interface for the NGS Map (the interactive web map application), serving as an enhanced landing page within the DDS. This updated “NGS Map” (replacing or evolving the current version at https://noaa.maps.arcgis.com/apps/webappviewer/index.html?id=190385f9aadb4cf1b0dd8759893032db ) will provide better access to geodetic control data, CORS stations, and other layers, improving visualization and querying for surveyors, GIS professionals, and the public.
    • These changes are part of the broader DDS rollout, currently pending beta release (as of February 2026), aimed at making data more accessible, visually rich, and compatible with the modernized NSRS components (e.g., NATRF2022, NAPGD2022, SPCS2022). The DDS landing page will consolidate access, moving away from legacy datasheet formats toward dynamic, web-based delivery.
    Accessing Data from NGS. (Presented at GeoWeek 2026)
    Accessing Data from NGS. (Presented at GeoWeek 2026)
    Accessing Data from NGS. (Presented at GeoWeek 2026)
    Accessing Data from NGS. (Presented at GeoWeek 2026)
    Accessing Data from NGS. (Presented at GeoWeek 2026)
    Accessing Data from NGS. (Presented at GeoWeek 2026)

    During Dan Gillins presentation he highlighted that NGS has three development phases for OPUS underway to support the Modernized NSRS:

    OPUS-S 5.2: Multi-GNSS with similar functionality as current OPUS-S

    • Occupations – one hour or greater
    • Standard deviations estimate instead of peak-to-peak values

    OPUS 6.0: Rewrite of code base in cloud-native application

    • single/multiple occupations on a single mark
    • enhanced sharing functionality
    • Occupation Time – minimum of 4 hours
    • NGS will review and add these data to the next reference epoch coordinate (REC) adjustment

    OPUS 6.1: Extension of OPUS 6.0 for multiple marks in a network

    • Replace OPUS-Projects functionality
    • Multiple occupations on a network of marks (campaign-style surveys)
    • Will allow multiple occupations on a single mark – uploads ~10 data files on a mark
    • Built for future expansion to support other geodetic measurements (classical, leveling)

    I want to emphasize that, in my opinion, NGS is doing a fantastic job with the limited resources that they have.  That said, I still have an issue with adopting the new NSRS without having a process for users to submit data to NGS for review, approval, and publication by NGS.  This may not be an issue if NGS’s OPUS 6.1 is available soon after the new NSRS is adopted by the Federal Agencies.

    My August 2025 GPS World Newsletter discussed the OPUS products under development and, as I mentioned at that time, in my opinion, may be a problem for some users.  As I stated in my August newsletter, for the new NSRS to be successfully implemented by users, it is essential that all the necessary software tools are available to enable users to submit projects for review, approval and publication by NGS. 

    Excerpt from August 2025 GPS World Newsletter

    “The NGS News announcement provides a list of products that will be available and a list of products that will not be available when the new NSRS is adopted. Users need to understand what products will not be available after NGS officially adopts the new NSRS so they can determine what that means to their workflow process and client requirements.  In my opinion, for the new NSRS to be successfully implemented by users, it is essential that all the necessary software tools are available to enable users to submit projects for review, approval, and publication by NGS.  As many of you know, when I worked for NGS, I was the Project Manager of the North American Vertical Datum of 1988 (NAVD 88). That said, from my experience as the NAVD 88 Project Manager, having the appropriate tools available was important for users to implement NAVD 88.  As a matter of fact, NGS accepted and processed vertical control data in both NGVD 29 and NAVD 88 for a period to assist users in the implementation of the new vertical reference datum.”

    NGS does state that users will be able to submit data through OPUS and OPUS Share to obtain estimates of coordinates in the new NSRS.  Unfortunately, using OPUS-Share results that are NOT official NSRS coordinates published by NGS could lead to confusing results and potential lawsuits since NGS does not stand behind the results and recommends NOT using OPUS-Share results for geodetic control.

    “This is NGS’s statement on OPUS-Share: Additionally, the popular function of “sharing” your solution with others (colloquially called “OPUS-Share”) will be retained, but with appropriate caveats that the shared solution should not be used as geodetic control. These shared solutions will be available through the geodetic mark pages of the DDS.“

    Why should users use OPUS-Share to establish geodetic control when NGS advises against relying on OPUS-Share for establishing geodetic control?  OPUS-Share results are not officially submitted to NGS for review, approval, and publication on an NGS Datasheet. I don’t believe this approach will meet the needs of users who require their projects to be reviewed, approved, and published by NGS.

    Finally, as someone deeply invested in the geodetic community—having retired from NGS and followed NGS developments closely for years—my overall opinion on the NSRS modernization rollout plan for the remaining products is cautiously positive, but with some genuine concerns that I believe NGS and stakeholders should address head-on to ensure a smoother transition.

    The phased beta release approach (starting in 2025 and continuing through 2026) is smart and user focused. Releasing components incrementally on the beta site, allowing at least 6 months of public testing and feedback per major piece (and overall testing extending beyond the final release), shows NGS is prioritizing stability over speed. The emphasis on stakeholder input, FGCS approval (now looking like late 2026 or early 2027), and a multi-month transition to the official site align well with best practices for such a massive shift. It’s encouraging to see private industry partners (e.g., ESRI, Blue Marble) already engaging deeply and planning implementations—success will depend on industry buy-in.

    That said, here are my main thoughts and concerns I’d share directly with NGS (perhaps via [email protected], user forums, or upcoming webinars/Q&A sessions):

    Timeline uncertainty: Clearer, more frequent milestone updates (beyond the Track Our Progress page) would help manage expectations. For example, monthly or bimonthly “status dashboard” with remaining beta items and projected release windows would be invaluable.

    OPUS and processing continuity: The shift away from OPUS-Projects 5 toward OPUS 6 and OPUS-Share is logical for a modern GNSS-centric system, but the lack of a firm end-of-support date for legacy OPUS tools (beyond “at least 6 months’ notice”) creates planning headaches for firms with ongoing projects. NGS should commit to a longer grace period—or ideally a defined parallel support window—for legacy OPUS tools (particularly OPUS-Projects 5) after the official adoption of the modernized NSRS.

    Data access and usability in the new DDS: The revamped Geodetic Mark/Station Pages, updated NGS Map interface, and overall Data Delivery System sound promising (more visual, integrated RECs/SECs, photos, etc.), but surveyors rely heavily on reliable, scriptable access (e.g., for bulk queries or automation). If the new web-based system lacks robust APIs or export options comparable to current datasheets/legacy tools, it could hinder efficiency. Beta testers should push hard on this during the 6+ month window.

    Transformation tools and legacy data handling: Enhanced web-based tools are key for bridging old-to-new (NAD 83/NAVD 88 to NATRF2022/NAPGD2022), but users need confidence that transformations minimize errors, especially in deformation-prone areas.

    Communication and outreach: NGS has improved with webinars, the Presentations Library, and beta feedback channels, and more targeted outreach to state agencies, professional societies (NSPS, AAGS), and software vendors has helped. That said, many in the field still feel “in the dark” about practical impacts—case studies, training resources, and FAQs tailored to common workflows would go far.

    In summary, the plan is thoughtful and deliberate, reflecting lessons from past delays. If NGS maintains transparency, incorporates feedback aggressively during beta, and ensures vendor readiness, the modernized NSRS will be a major win for accuracy, sustainability, and GNSS alignment.

    I’d encourage anyone reading this (including NGS staff) to test the beta products actively, submit detailed feedback, and participate in forums/Q&As. The community input will make or break the success of this once-in-a-generation update.

  • FGCS meets to address the National Spatial Reference System

    FGCS meets to address the National Spatial Reference System

    In last month’s GPS World newsletter, I mentioned that the National Geodetic Survey (NGS) would host a meeting of federal geospatial agencies under the auspices of the Federal Geodetic Control Subcommittee (FGCS). The purpose is to increase awareness and coordinate the NSRS Modernization across the government.

    The FGCS meeting took place on Wednesday, Jan. 21, 2026. This session was highly informative and played a key role in aligning federal agency engagement strategies and self-assessments in preparation for the final adoption of the modernized NSRS and its associated new datums.

    The FGCS holds a central position within the Federal Geographic Data Committee (FGDC). It coordinates geodetic activities across the federal government by

    • Developing and promoting standards
    • Advancing the use of authoritative geodetic control
    • Facilitating the modernization of the NSRS across agencies
    • Recommending the official adoption of the modernized NSRS by the FGDC as the foundational basis for geodetic control throughout the United States.

    The agenda for the Jan. 21 meeting is detailed in the section titled “Federal Geodetic Control Subcommittee Meeting.” This gathering supported broader efforts to raise awareness, ensure coordination and prepare agencies for the upcoming transition to the modernized NSRS, with formal approval and release anticipated later in 2027.

    Federal Geodetic Control Subcommittee Meeting

    January 21, 2026

    Agenda: 

    MC: Christine Gallagher

    TimeTopicPresenter
    1:00 – 1:15 pmWelcome and IntroductionsDaniel Roman
    1:15 – 1:20 pmNational Geodetic Survey (NGS) UpdateMarian Westley
    1:20 – 1:30 pmGeodetic Control Theme Update and its Modernization TimelinesDaniel Roman
    1:30 – 2:00 pm NGS Modernization Engagement Plan and ProgressDana J Caccamise II / Christine Gallagher
    2:00 – 2:15 pmBureau of Ocean Energy Management / Kearns & WestAndy Archer / Kyle Vint
    2:15 – 2:30 pmUS Census National Spatial Reference System (NSRS) Modernization PreparationVince Ossier / Josh Coutts
    2:30 – 2:40 pmBreak
    2:40 – 2:55 pmUS Department of Transportation NSRS Modernization PreparationAmy Nelson / Derald Dudley
    2:55 – 3:10 pmAmerican Society for Photogrammetry and Remote Sensing & National Society of Professional Surveyors Working Groups Chris Parrish / Linda Foster
    3:10- 3:50 pmDiscussion: Q&A from Agency presentations. What hurdles to implementation do you see or anticipate? Share your insights from internal working groupsGroup Discussion Moderator:  Dana J Caccamise II and Daniel Roman
    3:50 – 4:00 pmClosing Remarks Daniel Roman
    Adjourn to Silver Branch

    The meeting lasted three hours and covered a lot of material. Below are highlights; contact FGCS for the full meeting recording.

    Christine Gallagher, NGS, opened the FGCS session and introduced Dan Roman, NOAA’s National Geodetic Survey senior advisor for geodesy.

    Roman welcomed everyone and briefly outlined the meeting’s purpose. He then introduced Marian Westley, director of the Center for Operational Oceanographic Products and Services (CO-OPS) and current acting director of NGS.

    Westley’s remarks were brief but important. She noted CO-OPS manages tide gauges and is updating several datums in partnership with NGS, including the Great Lakes International Great Lakes datum. She said the United States and Canada, along with NOS and other federal agencies such as the Corps of Engineers, are heavily involved in Great Lakes management. She also reported that CO-OPS is updating the National Tidal Datum Epoch (current NTDE: 1983-2001) and is working closely with NGS to tie the updated NTDE to the new NSRS. See the image titled “The NTDE Update: New Tidal Datums are Coming!“

    During Roman’s comments, he highlighted the agencies and professional societies participating in the meeting presentations and provided an update on the latest rollout schedule for the modernized NSRS.

    He emphasized that this Jan. 21, FGCS meeting marks the start of a broader coordination process. The primary purpose of this high-level session was to facilitate the sharing of experiences, strategies, and best practices among federal agencies as they prepare for NGS’s NSRS modernization and the transition to the new reference frames and datums.

    Roman noted that future FGCS meetings will shift to a more technical and detailed focus. These subsequent sessions will allow agencies to present their self-assessment results, outline implementation strategies, and discuss progress toward adopting the modernized NSRS.

    Key objectives across these meetings include:

    • Collecting questions and feedback from participants,
    • Understanding user needs and required accuracy levels,
    • Identifying anticipated challenges during the transition,
    • Exploring opportunities for federal agencies to collaborate and support one another throughout the implementation process.

    This series of FGCS engagements aims to ensure coordinated, informed, and effective preparation across the federal government ahead of the final adoption and full rollout of the modernized NSRS.

    Here are a few key points based on Dan’s remarks:

    • Today’s presentations provide a broad overview of geospatial data modernization to inform departments about actions they may need to take and to start a dialogue about what each department is doing.
    • NGS encourages agencies to form working groups; those groups must define their own requirements and create migration plans, including assessing existing data, required accuracies, and the tools needed based on product accuracy statements.  [Note: My October 2025 GPS World newsletter highlighted organizations that are forming 2022 Reference Working Groups.]  NGS will designate points of contact to facilitate discussions and planning.
    • FGCS provides guidance on using geodetic data with various tools, models, and SOPs. User needs vary by accuracy: e.g., a 3-meter horizontal allowance (aids to navigation) is straightforward, while 3-centimeter requirements (e.g., FEMA Elevation Certificate) need more precise methods.
    • Several beta products released in July 2025 are being finalized, enabling the private sector to integrate them into services.  NGS is currently developing models and software to transform coordinates from the old datum to the new one. These models are expected around March, and in June/July NGS anticipates releasing an updated Beta NCAT tool to transform coordinates to the new datum. This tool will help users understand differences in local datums.
    • Final steps include FGCS recommendations for FGDC to adopt the new NSRS and to publish a Federal Register notice on the adoption of the modernized NSRS, anticipated to be completed in early 2027.

    After Dan Roman’s comments, Dana J Caccamise II gave a presentation describing NGS Modernization Engagement Plan and Progress.  Dana should get an award for material he has prepared and for his work to assist agencies and professional organizations in preparing for the new NSRS.  In my October 2025 GPS World Survey Scene newsletter, I highlighted the work of Dana J. Caccamise II, NGS regional geodetic advisor. Dana has developed vital guidance materials shared with federal agencies — such as the Federal Geographic Data Committee (FGDC) and professional organizations including the National Society of Surveyors (NSPS), American Society of Photogrammetry and Remote Sensing (ASPRS), and American Association for Geodetic Surveying (AAGS). 

    Here are a few key points based on Dana’s presentation titled “Visualizing Impact: Preparing for NSRS Modernization Through Geospatial Readiness and Collaboration.”

    • Caccamise said that what started as a focused task quickly grew into a broader strategic effort. He shared insights to encourage thinking about NSRS modernization not merely as a technical update but as a strategic business decision that will shape how agencies create, manage, and share basic data across programs, systems, and partnerships.
    • Caccamise briefly provided details to the U.S. Census. Before diving into modernization, he offered a personal glimpse of what it’s like to do a federal detail across agencies, noting he was fortunate to do a detail with the Census not long ago.
    Image: FGCS January 21, 2026, Public Meeting
    Image: FGCS Jan. 21, 2026, Public Meeting
    • Drawing on his experience, Caccamise emphasized the importance of cross-agency readiness and of building resilient trust and communication structures. While on detail at the Census, he was regularly surprised by new challenges, which made the work engaging; he strongly recommended that others take a detail at another agency if they have the opportunity. A key takeaway was the value of visualizing impact: beyond cataloging geospatial datasets, users must identify which support critical decisions, which are shared across agencies, and which risk becoming outdated if you don’t adapt. Mapping themes and workflows revealed real dependencies and, more importantly, vulnerabilities. That detail shifted his  focus from “what data do we have” to “what roles does this data play.”
    Image: FGCS January 21, 2026, Public Meeting
    Image: FGCS Jan. 21, 2026, Public Meeting
    • Efforts around NSRS modernization include a key product developed by Caccamise: the Ready Package. Designed to help agencies assess their readiness for NSRS modernization, the package includes communication tools, technical checklists, and talking points to support agency staff.
    Image: FGCS January 21, 2026, Public Meeting
    Image: FGCS Jan. 21, 2026, Public Meeting
    • He mentioned that from field-level GIS technicians to senior policy leads, everyone needs to understand what’s changing and why it matters. A key part of engagement is meeting people where they are. Dana has worked with agency partners to raise awareness, build interest, and strengthen understanding — not just of technical changes but of the organizational shifts needed for a smooth transition.
    • For agencies whose statistical workflows depend on spatially referenced data, that means ensuring location-based datasets remain accurate, comparable over time, and interoperable across programs when the reference system changes. Ultimately, this is about more than new coordinates: it’s about linking strategic planning to operational implementation, from data collection and integration to interagency coordination and informed decision-making.
    • He mentioned that the big question he’s hearing from many organizations is: how should customers and partners prepare for modernization?   He provided the following advice.  Start by evaluating your geospatial workflows to understand how the transition will affect data management, operations, and decision-making. Assess dependencies on NGS products and services to ensure continued access and interoperability and proactively identify challenges and opportunities – he mentioned that NGS can’t do this for you because each agency’s situation is unique. Address potential impacts early to reduce operational risk by finding weak points before they cause surprises. Act now: preparing early will minimize future cost and complexity.
    Image: FGCS January 21, 2026, Public Meeting
    Image: FGCS Jan. 21, 2026, Public Meeting
    • For example, working with the Census under the current national spatial reference system highlights the geographic scope of some operational areas, which span multiple tectonic plates as modeled in the modernized NSRS. Even small regional differences can affect how location-based data are collected, integrated, and compared — especially for programs that need consistent, long-term geospatial baselines. Today, federal agencies commonly use three reference systems — NAD27, NAD83, and WGS84, which complicates geospatial data management.
    • The Census is a major user and producer of geospatial data, relying on GIS to support operations. This includes the MAF/TIGER geographic database, which contains roads, rail lines, hydrography, landmark features, and legal and statistical boundaries.
    • Along with many other critical datasets, the Census’s collaborative spatial and statistical research is more effective and interoperable when grounded in a common reference system, such as the National Spatial Reference System.
    Image: FGCS January 21, 2026, Public Meeting
    Image: FGCS Jan. 21, 2026, Public Meeting
    • Because these datasets are inherently geospatial, many, especially those requiring high positional accuracy or relying on external references such as airborne or satellite data, will be affected by NSRS modernization. The update will enable more consistent data stewardship and support integrated spatial analytics, helping align with individual agency spatial data strategies. Bureau-level geospatial work becomes more effective and future-ready when supported by a modern, shared spatial reference system like the NSRS.
    • One of the biggest risks is cultural, not technical. If the NSRS is treated as just another dataset, rather than an enabling framework, the foundation for other systems weakens. When the NSRS is recognized as the framework, everything built on it has a solid base. You can’t manage risk if you can’t measure it—and the NSRS is how we measure. Here are a few practical examples.
    • Floodplain mapping and storm surge models depend on accurate vertical data. Errors of even a foot can leave neighborhoods unprotected or cause unnecessary regulation.
    • In transportation, subsidence is a hidden risk: roads and bridges may seem fine until precise geometric monitoring reveals sinking.
    • Shoreline change is a growing challenge; coastal communities need accurate shoreline monitoring for planning and insurance.
    • In public safety, emergency response relies on precise locations — from 911 calls to field deployments. Seconds and meters matter when lives are on the line.
    Image: FGCS January 21, 2026, Public Meeting
    Image: FGCS Jan. 21, 2026, Public Meeting
    • As Roman mentioned, Caccamise also stated that the modernized NSRS is being released in phases. Initial beta releases are available now for testing and evaluation—not final production. NGS plans to release the remaining components in beta during this calendar year. The modernized NSRS will replace the current datums at least six months after the final preliminary component is released, giving partners time to review the beta and provide feedback. Near the end of this period, FGCS will convene to discuss and socialize the modernization details and the planned datum replacement.

    Next steps for your agency’s modernization:

    • Evaluate operational needs and identify changes that aren’t necessary.
    • Assess organizational impacts and staff readiness—are teams prepared for modernization?
    • Determine how existing programs and regional support will be affected.
    • Collaborate with partner agencies to align shared datasets, reduce redundancy, and maximize efficiency.
    • Prioritize leadership and communication to ensure the organization understands the changes.
    • Plan for future improvements in spatial accuracy, even if you don’t need them immediately.
    Image: FGCS January 21, 2026, Public Meeting
    Image: FGCS Jan. 21, 2026, Public Meeting
    • As noted by Dan Roman, Dana Caccamise also highlighted that many lower-accuracy datasets may not require coordinate changes beyond updating their metadata—typically those with spatial accuracy on the order of 10 ft or worse. However, he also noted an important caveat: many operational workflows don’t actively read or enforce metadata. In those cases, the risk is not the dataset itself but the accuracy context that becomes embedded as data moves through systems.
    • An early, critical step is therefore to identify not only which datasets are likely unaffected but also how those datasets are consumed, transformed, and reused. That approach prevents unnecessary work and avoids unintended downstream impacts. Remember: NSRS modernization is more than a technical update, it’s an opportunity to strengthen your agency’s future geospatial capabilities.
    • Now, I know this newsletter is long, but I would like to highlight one more presentation that I believe provides a model for other agencies to follow.  That is, the presentation of the Department of Interior’s Bureau of Ocean Energy Management (BOEM) activities presented by Kyle Vint (Vice President, Kearns & West) – “From Proactive Engagement to Lasting Impact: BOEM’s Path to Datum Readiness.” 
    Image: FGCS January 21, 2026, Public Meeting
    Image: FGCS Jan. 21, 2026, Public Meeting

    Kearns & West is a communications and engagement specialization firm.  The materials that they develop to support internal communications and outreach within an organization are available for other organizations. They provided a QR code for others to access their resources.

    Vint outlined BOEM’s operating context and described how the agency is proactively addressing NSRS modernization, including several strategies.

    Image: FGCS January 21, 2026, Meeting
    Image: FGCS Jan. 21, 2026, Meeting

    BOEM’s challenges are partly historical: until about 2010, it was part of a parent agency that has since split into three separate agencies. That fragmentation means BOEM must coordinate data and change management not only internally but across three agencies that share data centers and geospatial datasets. BOEM relies on authoritative geospatial data to manage offshore energy and mineral activities on the Outer Continental Shelf; BOEM’s Geospatial Services Division supports this by maintaining leases and boundaries that underpin program decision-making. Because the ocean serves many purposes, BOEM relies on multiple layers of information from different agencies to support those decisions.

    BOEM’s path to modernization is further complicated by internal organizational factors. The agency struggled with the NAD27-to-NAD83 transition due to resource constraints and misunderstandings — some staff believed modernization would alter legal lease blocks, which they expected to be immutable — so the transition was not fully implemented.

    Image: FGCS January 21, 2026, Meeting
    Image: FGCS January 21, 2026, Meeting

    BOEM holds large datasets in both NAD27 and NAD83, fragmenting its workflow. Maintaining and converting between multiple reference systems is labor-intensive and introduces inconsistencies.

    BOEM must dedicate substantial staff time to managing data in multiple reference systems. BOEM’s Geospatial Services Division recognized early that continuing workarounds would increase risk over time, so they began proactive modernization planning.

    The Geospatial Services Division saw this as more than a technical issue — it’s also a people, communication, and resourcing challenge. BOEM shifted from fragmented efforts to a proactive, multi‑year planning approach emphasizing governance, leadership buy‑in, and clear communication. The Geospatial Services Division established a milestone‑based approach for consistent messaging and coordination across stakeholders and offers internal expertise to support programs and regions as they assess costs and technical complexity.

    Their strategy seeks common ground to pool resources for shared problems and to use the Geospatial Services Division as an internal augmentation so individual offices aren’t forced to opt out. This reduces cost uncertainty and enables realistic planning for timelines and required participants.

    Image: FGCS January 21, 2026, Public Meeting
    Image: FGCS January 21, 2026, Public Meeting

    As part of the process, user personas were created to identify who would struggle with each step and who would benefit from early, sustained engagement. For each group, they defined the value of participating and explained why they were invited.

    BOEM leaderships were treated like investors—they ensured they brought geospatial experts to meetings so questions could be answered, and so leadership had actionable budget information for long‑term planning. At the program and regional level, data experts who know existing datasets, reference systems, dependent applications, and potential workflow challenges were part of the process.

    They also documented internal roles so others can model the approach. The Geospatial Services Division coordinates the effort across the organization. Program and regional experts provide domain knowledge. Kearns & West (technical and communications contractors) supported messaging, prepared materials, and ran meetings so BOEM staff could focus on the conversation. Clear roles and sustained engagement have been critical in this multi‑year planning effort.

    Image: FGCS January 21, 2026, Public Meeting
    Image: FGCS January 21, 2026, Public Meeting

    The team developed a Survey and sent it to each program and region to gather resource requirements. The survey asked what data they have and its characteristics, which applications or workflows depend on that data and could be affected by modernization, and what technical resources they expect will be needed to support budgeting.

    Image: FGCS January 21, 2026, Meeting
    Image: FGCS January 21, 2026, Meeting

    As part of the process, they are building internal champions to advocate for the effort, simplifying complex issues so staff can brief leadership, and convening agencies, partners, and industry to co-create solutions.

    Finally — thanks for sticking with this lengthy newsletter. I know it’s long, but the information is important for federal agencies and their contractors. One more item: a key session is scheduled for GeoWeek — “Roundtable – NSRS Modernization and Professional Societies” — on 02/18/2026 at 10:30 AM. See the box titled “Roundtable – NSRS Modernization and Professional Societies” for presentation and speaker details.

  • A New Year’s resolution for National Spatial Reference System users

    A New Year’s resolution for National Spatial Reference System users

    Happy New Year! I’ve always felt that a fresh calendar represents a world of new opportunities, and I wish you all a fantastic 2026. For many, this is a season for reflection and self-improvement, with goals typically centered on fitness, faith, personal growth or career milestones.

    As regular readers of this newsletter know, my primary focus over the past year has been to champion the importance of geodesy and to prepare the geospatial community for the National Geodetic Survey’s modernized National Spatial Reference System (NSRS).

    To see how modern tech would handle such a specialized professional niche, I asked the AI chatbot Grok: “What would be a good New Year’s resolution for a user of the National Spatial Reference System?”

    The response was quite insightful. Take a look at what it suggested below.

    What would be a good New Year’s Resolution for a user of the National Spatial Reference System? (Grok’s Response)

    Fun and Practical New Year’s Resolutions for NSRS Users

    As we head into 2026, the modernization of the NSRS is in full swing. NOAA’s National Geodetic Survey (NGS) released the first beta products in June 2025, with ongoing rollouts and testing throughout the year. The full transition to new frames like NATRF2022 and NAPGD2022 is expected soon, bringing centimeter-level accuracy aligned with GNSS and global standards—but it requires preparation.

    Here are some timely, geodesy-inspired New Year’s resolutions tailored for surveyors, GIS professionals, engineers, and anyone relying on the NSRS:

    1. Fully transition workflows to the modernized NSRS. Commit to updating software, processes, and datasets for the new terrestrial reference frames and geopotential datum. Test tools on the NGS Beta site and provide feedback to help shape the final rollout.

    esri.com

    gpsworld.com

    1. Achieve new heights (and accuracies) in 2026. Embrace NAPGD2022 for more precise orthometric heights. Resolve to reprocess key projects with updated transformations (via NCAT or VDatum) and say goodbye to NAVD 88 quirks.
    1. Stay grounded in best practices. Incorporate the latest NGS guidelines, like NOS NGS 92 standards for GNSS surveys. Attend webinars and workshops, or review resources, to keep your positioning sharp.

    gpsworld.com

    1. Contribute to the system. Submit high-quality GNSS data via OPUS-Share or participate in crowdsourced efforts to improve the network. Help make the NSRS even more robust for everyone.
    1. Measure progress monthly. Track how the modernization impacts your work—review coordinate shifts, audit legacy data, and plan for smoother integrations in future projects.

    These resolutions blend practicality with the spirit of improvement that defines geodesy. Happy New Year—may your positions be accurate, your elevations precise, and your datums forever modernized! For the latest updates, check geodesy.noaa.gov.

    It’s no surprise that Grok highlighted the NSRS modernization; it even incorporated a photo of a geodetic benchmark I took for my July 2025 GPS World Survey Scene newsletter.

    Understanding that most AI chatbots personalize results using past interactions (unless disabled), I wanted to test this. After clearing my cache and deleting all previous Grok interactions, I posed the question again.

    You can find that second, impersonalized response below.

    Second Response from Grok

    What would be a good New Year’s Resolution for a user of the National Spatial Reference System? Grok’s Second answer.

    Here are some practical, realistic, and useful New Year’s resolutions tailored for someone who regularly works with the NSRS whether you’re a surveyor, GIS professional, geodesist, engineer or data manager:

    1. “This year, I will stop mixing epochs without documenting them.” Resolve to always record the reference epoch (e.g., 2010.0, 2020.00) when I use NAD83(2011), NAD83(CORS96), NAD83(2011) epoch-specific coordinates, or when I transform to ITRF2020/2020.0. Bonus: add epoch to layer names and metadata.
    2. “I will run OPUS or CSRS-PPP at least once a month to keep my local control fresh.” Make it a habit to periodically re-observe a trusted point and submit it to NOAA’s OPUS (or CSRS-PPP in Canada) to verify that my local network hasn’t drifted too far from the national datum.
    3. “I will finally transition at least one active project to the modern NSRS (NAD83(2011)/NAVD88 → NATRF2022 / NAPGD2022).” Pick one ongoing or new project and do the full datum shift. Learn the tools (NADCON5, VERTCON3, GEOID18 → GEOID2022) and document what changed.
    4. “I will replace every ‘NAD83’ label that doesn’t specify an epoch or realization with something more precise.” No more generic “NAD83” in reports, plats, or metadata. Aim for “NAD83(2011) epoch 2010.0” or “NAD83(2011) CORS-derived” — or better yet, start using NATRF2022 when appropriate.
    5. “I will learn to use the NGS Coordinate Conversion and Transformation Tool (NCAT) fluently.” Commit to doing at least 5 conversions or transformations per month in NCAT instead of relying on old software or hand-calculated factors.
    6. “I will check the NGS Data Explorer / Datasheet for every benchmark or CORS I plan to use — before I use it.” No more assuming a published value is still good. Make it a 2-minute ritual to look up the latest adjusted position and velocity.
    7. “I will attend at least one NGS webinar or read one Bluebook chapter in 2026.” The NGS webinar series is free and excellent. Pick one session (e.g., on GEOID2022, NATRF2022 implementation, or GNSS vector processing) and actually watch it.
    8. “I will prepare a small ‘before/after’ datum comparison report for my organization or clients.” Quantify what the 2022–2025 NSRS modernization means in your typical project area (horizontal shift, orthometric height change). Even a one-page summary builds understanding and credibility.
    9. “I will stop treating GEOID18 as the final word and start using GEOID2022 for new work.” Especially important for projects that will live past 2025, as NGS is phasing out support for older geoids.

    Pick one or two that feel achievable and most relevant to your day-to-day work. My personal favorite starter resolution for most NSRS users in 2026: “In 2026, I will clearly label the datum, realization, epoch, and geoid model on every deliverable I produce.”

    That one habit alone dramatically reduces confusion downstream.

    I really appreciate Grok’s responses because they address crucial issues that many geospatial users either overlook or take for granted, emphasizing the importance of proper documentation and associated metadata.

    Key Resolution Examples:

    • Specificity: “I will replace every ‘NAD83’ label that doesn’t specify an epoch or realization with something more precise.”
    • Verification: “I will check the NGS Data Explorer / Datasheet for every benchmark or CORS I plan to use — before I use it.”

    It is important to note that the AI chatbot assumes the modernized NSRS has already been adopted, which, as of January 2026, is not the case. This highlights that AI still has limitations and requires human oversight.

    I challenge you to ask your own AI chatbot a similar, niche question related to your profession and compare its responses.

    Beyond the specific technical corrections, Grok provided excellent general advice for any geospatial professional. Take, for example, action items 1 and 5 from its first response:

    • Transition Workflows: Commit to fully updating software, processes, and datasets to align with the new terrestrial reference frames and geopotential datum.
    • Measure Progress Monthly: Track the real-world impact of modernization by reviewing coordinate shifts, auditing legacy data, and planning for smoother integrations in upcoming projects.

    Even though the modernized NSRS has not yet been officially adopted as of January 2026—with official release and FGCS approval expected later this year—following these steps now ensures you are prepared for the official transition when it occurs.

    So, how do we put this advice into action? In my October 2025 GPS World Survey Scene newsletter, I highlighted the work of Dana J. Caccamise II, NGS regional geodetic advisor. Dana has developed vital guidance materials shared with federal agencies—such as the Federal Geographic Data Committee (FGDC) and professional organizations including National Society of Surveyors (NSPS), American Society of Photogrammetry and Remote Sensing (ASPRS), and American Association for Geodetic Surveying (AAGS). 

    To help your team prepare for the official transition later this year, I’ve included a box titled “Questions to Guide a Self-Assessment of Your Operation and Products.” These questions, originally featured in my October newsletter, are designed to ensure your organization is fully equipped to implement the new NSRS the moment it is adopted.

    Questions to Guide a Self-Assessment of Your Operation and Products

    1. Are you generating or using geospatial data (or doing both)?
      • If so, your workflows are likely dependent on geodetic control tied to one or more NGS products. The upcoming NSRS update will affect these dependencies. (See the box titled “List of NGS Products and Services.”)
    2. Do you know if your mission, project, or datasets depend on NGS products?
      • Identifying whether and how your entity relies on NGS products is a critical first step in assessing potential impacts.
    3. What are your accuracy, precision, and shelf-life requirements for geospatial data?
      • Understanding your mission’s specific data requirements ensures you can evaluate whether NSRS modernization will meet your operational needs without unnecessary adjustments.  This should include plans to accommodate greater accuracy in the future.
    4. Do you know how your entity accesses and utilizes geospatial data?
      • Are you obtaining it directly from NGS or indirectly through third-party vendors (e.g., RTN systems, GIS platforms, GNSS companies)?
      • Many entities rely on geodetic control without realizing it. NGS’s foundational data and frameworks are often invisible and seamlessly embedded within the tools and services offered by third-party vendors, such as GIS platforms, survey equipment, and software providers. These vendors, in turn, depend heavily on NGS products like the NSRS to ensure their tools are accurate and functional. Understanding this indirect reliance is crucial for preparing your workflows and ensuring continuity as the NSRS is modernized.
    5. Where does your entity fit in with the geodetic workflow?
      • Does your entity create integral products (e.g., GNSS data, Lidar data) on which other products depend?
      • Evaluating these dependencies will help you determine the scope of NSRS modernization impacts.
    6. What are your project requirements for data accuracy and longevity?
      • Assess whether your data accuracy thresholds and long-term usability align with the modernized NSRS.
    7. Have you evaluated workflows and identified potential impacts in areas affected by significant ground movement (e.g., regions with tectonic shifts, vertical land motion, and, most notably, subsidence) 
      • Identifying potential risk or disruption areas can guide prioritization and help mitigate impacts on critical operations.

    In my October 2025 GPS World newsletter, I mentioned that the National Geodetic Survey (NGS) would be hosting a meeting with Federal geospatial agencies under the auspices of the Federal Geodetic Control Subcommittee (FGCS). The purpose is to increase awareness and coordinate the NSRS Modernization across the government.

    While the original meeting scheduled for October 15, 2025, was canceled due to the Federal Government Shutdown, it has been officially rescheduled for Wednesday, January 21, 2026. This meeting will be critical for aligning agency engagement strategies and self-assessments ahead of the final adoption of the new datums.

    As stated in my October 2025 newsletter, the primary objectives of this meeting are to:

    • Increase awareness of the National Spatial Reference System (NSRS) Modernization rollout schedule and engagement strategy, including self-assessment and interaction between official departmental working groups and an NGS point of contact.
    • Within other Departments, connect decision-makers to those who accomplish NSRS modernization tasks and designate points of contact to interface with NGS capacity-building efforts.
    • Share experiences and strategies among federal agencies concerning NSRS Modernization self-assessment and preparation.
    • (New) Formally transition the foundational beta products (released in May 2025) from preliminary to final.
    • Gather questions, discuss anticipated challenges, and identify opportunities to support each other through this transition.

    The FGCS plays a central role in coordinating geodetic activities across the federal government, including the development of standards and the promotion of the use of authoritative geodetic control (e.g., CORS, geoids) to ensure that geospatial data is accurate, accessible, and interoperable, and to advance the modernization of NSRS across agencies and recommend the adoption of the modernized NSRS by FGDC as the official basis for geodetic control in the United States. It is my understanding that this meeting is open to the public (virtually) for listening and observation.  The box titled “Federal Geodetic Control Subcommittee Meeting” provides the agenda of the January 21, 2026, meeting.

    Federal Geodetic Control Subcommittee Meeting Agenda held January 21, 2026.
    Federal Geodetic Control Subcommittee Meeting Agenda held January 21, 2026.

    To join the meeting virtually, registration is required. You can find all the necessary details and a direct link to sign up in the box titled “Registration for the Virtual Attendance of the Meeting.”

    Registration for the Virtual Attendance of the Meeting

    NOAA’s National Geodetic Survey (NGS) invites you to the upcoming Federal Geographic Data Committee (FGDC) Federal Geodetic Control Subcommittee (FGCS) meeting.

    • Date: Wednesday, January 21, 2026
    • Time: 1:00 PM – 4:00 PM ET
    • Location: Hybrid meeting, offering both in-person attendance at NOAA Offices in Silver Spring, MD, and virtual participation via WebEx.
      • If you plan to attend in person, please email [email protected] so we can ensure building access.

    If you plan to attend virtually, here is the registration link: https://ngs-nos-noaa.webex.com/weblink/register/r53ab4d202de3bb20df12d9364862ff0f

    As I mentioned in my October 2025 GPS World Survey Scene newsletter, several organizations have formed working groups to address the new NSRS. The National Society of Surveyors (NSPS) has released a story map to inform the professional surveying community and is developing guidance and case studies. The American Association for Geodetic Surveying (AAGS) is collaborating with NSPS. The American Society of Photogrammetry and Remote Sensing (ASPRS) has prepared materials available on its website.

    In October 2025, NSPS held its Fall meeting.  The box titled “Excerpts from 2025 NSPS Fall Meeting Report: October 17, 2025” contains excerpts from the report provided by Richard Kleinmann, Wisconsin NSPS Director, on the working group’s activities being performed by the National Society of Professional Surveyors (NSPS) Professional Standards NSRS Modernization Subcommittee.

    Excerpts from 2025 NSPS Fall Meeting Report: October 17, 2025

    Submitted by: Richard Kleinmann PLS, Wisconsin NSPS Director

    Subcommittee Purpose: To promote awareness, adoption, and readiness for the implementation of the Modernized National Spatial Reference System (NSRS) in cooperation with the National Geodetic Survey (NGS) and other geospatial groups.

    Activities: NSPS leadership and the NSRS Modernization Subcommittee continue to work closely with NGS to promote awareness, adoption, and readiness for the new 2022 datums, which are expected to be approved sometime in 2026. Due to federal funding challenges occurring in 2025, NSPS felt it necessary to intensify its support of NGS and the modernization of the NSRS which was the genesis of this subcommittee.

    As an outgrowth of interactions between NSPS & NGS during NGS quarterly meetings and at geospatial events such as the ESRI User Conference and Geo Week, the NSPS leadership team, and subsequently the NSRS Modernization Subcommittee, began developing a suite of resources — including an ArcGIS StoryMap with several resources useful for the transition.   See the link for the NSPS ArcGIS Story map here: https://share.google/oOAIapPQnux5q8nwl

    The NSRS Modernization Subcommittee is also working on a series of documents originally developed by Dana J. Caccamise of NGS intended to be used by Federal Agencies in the transition to the new datums.  We are adapting the documents to change the “voice” from NGS to NSPS and the intended audience to state, regional, county and local agencies, as well as private practitioners, to help them transition smoothly to the modernized NSRS.  At this point, the document package includes:

    • Initial outreach tools (Email & Leadership Memo), 
    • Technical readiness resources (Self-Assessment Checklist & Survey)
    • Briefing materials for agency coordination (Presentation Template)

    These document resources are being developed with the hope to share them via NSPS social media outreach efforts and possibly a geospatial information “hub” shared by NSPS and other geospatial organizations.

    Proposed Whitepapers/Use Case Reports: The intent of these whitepapers is to is to provide a somewhat higher-level view of how the transition to the new datums/frames can be accomplished by showing what tools are available and what to consider when designing a project approach.  Our hope is to promote the adoption of the new datums and share the benefits of doing so.  Basically, adopting a “be prepared, not scared” attitude.  We are looking for people willing to share their solutions so others can benefit from their experience and be more likely to be early adopters.  It is not our intent to develop detailed step by step recipes that can be blindly followed because every geographic region has their unique circumstances that need to be considered but the white papers will instead supply the foundation for them to confidently build a project approach that works in their situation.

    Coordination with other working groups: NSPS is looking forward to coordinating with similar Working Groups that NGS has encouraged to be formed by the American Society for Photogrammetry and Remote Sensing (ASPRS) and the American Association for Geodetic Surveying (AAGS). There are several Task Forces and Committees formed on the state level that are also working on adoption and implementation issues specific to their states.  Together, these efforts aim to build understanding, reduce uncertainty, and support the geospatial community’s successful implementation of the updated reference framework.   NSPS and NGS have committed to having a significant presence at Geo Week in Denver, Colorado, on February 16-18, 2026. 

    As mentioned in the working group’s report, “As an outgrowth of interaction between NSPS & NGS during NGS quarterly meetings and at geospatial events such as the ESRI User Conference and Geo Week, the NSPS leadership team and subsequently the NSRS Modernization Subcommittee began developing a suite of resources — including an ArcGIS StoryMap with several resources useful for the transition.   See the link for the NSPS ArcGIS Story map here: https://share.google/oOAIapPQnux5q8nwl.

    The box titled “NSPS ArcGIS Story Map” offers a detailed look at this resource, which visually illustrates the impact and benefits of the upcoming NSRS modernization.

    NSPS ArcGIS Story Map
    NSPS ArcGIS Story Map

    The website has five buttons:

    • Overview
    • What to Expect
    • How to Prepare
    • Resources
    • Note to Users

    The section titled “The Overview Section” details the essential information — who, what, where, when, and why — regarding the new, modernized NSRS.  Additional information is available on the website.

    Overview

    WHO: The  National Geodetic Survey  (NGS), located within the National Oceanic and Atmospheric Administration (NOAA) of the United States government.  The NGS is responsible for defining, maintaining, and providing access to the country’s positioning infrastructure called the  National Spatial Reference System  (NSRS).

    WHAT: Is updating the NSRS  – horizontal (geometric, NAD 83) and vertical (geopotential, NAVD 88 and local island vertical datums PRVD02, USVI09, ASVD02, GUVD04, HAWAII – Local Tidal) geodetic datums, an effort that has been underway since 2007.

    WHERE: The North American, Pacific, Caribbean, and Marianas plates.

    WHEN: Now – rollout is underway. An updated  Federal Register Notice was released on October 9, 2024.   Alpha and  Beta products are being released, with full replacement of the NSRS anticipated in 2026.

    WHY: These datums have been in use since GPS was in its infancy – i.e., for decades, and there are known limitations that the new system addresses:

    • NAD 83 is not as geocentrically defined as today’s positioning technologies demand, meaning not referenced to the center of Earth’s mass, by about 2.24 meters based on the latest international estimates. This is problematic when using Global Navigation Satellite Systems (GNSS), which orbit about and provide positions relative to the center of the Earth.
    • NAD 83 grouped the North American and Caribbean plates in its definition.  The updated system has broken those two plates out (because we now understand how to measure how the plates rotate individually) in addition to the Pacific and Marianas plates included in NAD 83, resulting in definitions for four Terrestrial Reference Frames (TRFs): NATRF2022, PATRF2022, MATRF2022, and CATRF2022.
    • Continental drift and vertical land movement were not accounted for in the existing NSRS.  Reference epochs (timestamps, for instance) for coordinates have been introduced for survey data to help us better understand movement or change over time.
    • Based on current international geoid estimates, NAVD 88 is biased by approximately 1.5 meters and tilted by 1 meter coast-to-coast.
    • There are currently multiple vertical datums.  The new system will consist of one.
    • NAD 83 and NAVD 88 were designed independently, resulting in reduced accuracy.  In the new system, they were designed together, resulting in better integration and higher accuracy.
    • GEOID 18 and previous models were hybrid models “warped” to match leveled benchmarks. GEOID2022 will be a more consistent and stable model as it is a purely gravimetric geoid model.
    • Currently, both physical marks and continuously operating GNSS stations are relied upon for the existing NSRS. Physical marks degrade and are destroyed over time, negatively affecting height and position data. The modernized NSRS will rely exclusively on GNSS stations.
    • State Plane Coordinate System 83 (SPCS 83) includes high levels of distortion for many areas. The modernized SPCS2022 minimizes distortion or scale error (the difference between ground and grid measurements) at the topographic surface rather than the reference ellipsoid surface, and is designed to minimize distortion in populated or high-use areas.
    • An important change between SPCS 83 and the upcoming SPCS2022 is that only the international foot (1 foot = 0.3048 meter, exactly) will be supported, which differs from SPCS 83, with some states officially using the international foot while others use the U.S. survey foot (1 foot = 1200/3937 meters). This is consistent with the  deprecation of the U.S. survey foot initiated by the National Institute of Standards and Technology (NIST) at the end of December 2022.

    The website makes it easy to spread the word about NSRS modernization. By clicking the share button on the right side of the page, you can access several ways to distribute the story map with colleagues or on social media.

    The Sharing the NSPS ArcGIS Story Map includes more details — it even includes an embedded QR code that you can scan to open the map directly on your mobile device.

    You can access it on your mobile device using the code below.

    NSPS ArcGIS Story Map QR Code
    NSPS ArcGIS Story Map QR Code

    For those who prefer a physical copy or a clean PDF, the site also offers a print-friendly version. See the box titled “NSPS ArcGIS Story Map – Print View” for instructions on how to access it. This 15-page document provides all the same information as the interactive site in a consolidated, easy-to-read format.

    NSPS ArcGIS Story Map – Print View
    NSPS ArcGIS Story Map – Print View

    As highlighted in the NSPS working group’s October report, both NSPS and NGS are committed to a major presence at Geo Week in Denver, Colorado, from February 16–18, 2026.

    A key session, “NSRS Modernization – The Latest Technical Updates,” is currently scheduled for February 17, 2026, at 2:00 PM. For more details on the presentation and speakers, refer to NSRS Modernization – The Latest Technical Updates below.

    2:00 PM – 3:30 PM MT

    Bluebird Ballroom 1A

    The National Spatial Reference System (NSRS) is undergoing a major transformation to provide more accurate, accessible, and consistent geospatial reference data across the United States. This session will present the latest technical updates on NSRS modernization, including advancements in geodetic reference frames, updated survey standards, and enhanced tools for positioning and measurement. Attendees will learn how these changes impact surveying, mapping, infrastructure, and engineering projects, and gain practical guidance for integrating modernized NSRS data into workflows. This session is essential for professionals seeking to stay current with the evolving national geospatial reference framework.https://mail.google.com/mail/u/0/#search/lfoster%40esri.com/FMfcgzQcqtcPbfppZtnTpZZWDMkQcXfk?projector=1&messagePartId=0.1

    I wish you all a prosperous 2026 filled with wonderful new relationships, exciting opportunities, and continued happiness and success.

    Happy New Year!

  • Are you ready for NSRS modernization? What the upcoming changes mean for your geospatial data

    Are you ready for NSRS modernization? What the upcoming changes mean for your geospatial data

    In my August 2025 GPS World newsletter column, I highlighted that a colleague reminded me that the National Geodetic Survey’s (NGS) new National Spatial Reference System (NSRS) is more than a technical upgrade. It offers a prime opportunity to review and improve current processes and workflows, examine existing products and considerations, and plan strategically for future needs. By auditing geospatial data dependencies now, NSRS users can assess how transitioning to the new datum will affect workflows, datasets and operational decision-making.

    Several organizations have formed working groups to address the new NSRS. The National Society of Surveyors (NSPS) has released a story map to inform the professional surveying community and is developing guidance and case studies. The American Association for Geodetic Surveyor (AAGS) is collaborating with NSPS. The American Society of Photogrammetry and Remote Sensing (ASPRS) has prepared materials available on its website. Additionally, under the leadership of Gary Thompson, the North Carolina Geodetic Survey established the North Carolina 2022 Reference Frame Working Group. The group’s goal is to address issues related to the implementation of the datum change in 2026. It includes representatives from North Carolina agencies involved in producing or using geospatial products and services.

    Agencies Involved in the NC 2022 Reference Frame Working Group
    NC Geodetic SurveyNC DOT HydraulicsNC State Mapping Advisory Committee
    NC Geographic Information Coordinating Council (GICC)NC State, Land Records ManagementNC Geodetic Survey Advisory Committee
    NC Center for Geographic Information & AnalysisNC GICC Local Government CommitteeNC Society of Surveyors
    NC DOT State Location & SurveysNC State Mapping Advisory CommitteeDuke Energy
    NC DOT Photogrammetry UnitNC GICC Local Government CommitteeU.S. National Geodetic Survey

    The organizations participating in the NC RFWG are assessing how changes in the new NSRS may impact their geospatial workflows and evaluating their reliance on NGS products and services. Proactive self-assessment is essential because NGS cannot customize support for each entity’s unique needs and processes. By identifying potential challenges and opportunities early, organizations can adapt smoothly and maintain operational efficiency during the transition. The following were the key action items from the last NC RFWG meeting:

    • Create an information sheet to help local governments prepare for the data change
    • encourage agencies to consult their software vendors on support measures for the new datums
    • establish a rule for when to use the U.S. Survey Foot versus the International Foot
    • review current data files to ensure their metadata includes datum and unit information.

    Many participants of the North Carolina working group expressed interest in understanding how much the coordinates will shift with the new NSRS. While NGS’s website offers diagrams that provide a high-level overview of coordinate and product changes, many users sought more detailed information specific to North Carolina. To address this, I used NGS’s Multi-Year CORS Solution 3 (MYCS3) update of the NOAA CORS Network to ITRF2020, epoch 2020.0, to estimate the changes between the current NSRS — NAD 83 2011 (epoch 2010.0) — and the upcoming NSRS in North Carolina, such as NATRF2022 at epoch 2020.0. This approach offers a more detailed view of the magnitude of shifts in local regions. The figure titled “Approximate Differences Between NATRF2022 (Epoch 2020.0) and NAD 83 2011 (Epoch 2010.0) in NC” illustrates the approximate horizontal coordinate differences between the current NSRS and the future NSRS based on NCN CORS data. (Note that these units are in feet.) For additional information on MYCS3 and regional changes across the United States, refer to my August 2025 GPS World column.

    Approximate differences between NATRF2022 (Epoch 2020.0) and NAD 83 2011 (Epoch 2010.0) in North Carolina. Horizontal change in feet. (Credit: Dave Zilkoski)
    Approximate differences between NATRF2022 (Epoch 2020.0) and NAD 83 2011 (Epoch 2010.0) in North Carolina. Horizontal change in feet. (Credit: Dave Zilkoski)

    Differences in orthometric heights between the new NAPGD2022 and the current NAVD 88 are significant for anyone working with FEMA flood maps or preparing flood insurance elevation certificates. I used ITRF2020, epoch 2020.0, ellipsoid heights from NOAA CORS stations along with Geoid2022 values to estimate the NAPGD2022 orthometric heights at the CORS sites. As depicted in the plot, the height differences between NAPGD2022 and NAVD 88 across North Carolina range from about 0.5 feet in the southeastern region to over a foot in the northern and western regions. (Note that the units are in feet.)

    Approximate differences between NAPGD2022 and NAVD 88 in North Carolina. Orthometric height change in feet. (Credit: Dave Zilkoski)
    Approximate differences between NAPGD2022 and NAVD 88 in North Carolina. Orthometric height change in feet. (Credit: Dave Zilkoski)

    This type of information should be shared with managers of real-time GNSS networks(RTN). RTN operators could then establish a parallel beta system to enable users to understand how the new NSRS may affect their products and services. (Note: The North Carolina Geodetic Survey, which manages the NC CORS/RTN system, is considering running a pilot parallel RTN based on the new NSRS.) This data can be valuable for RTN users to assess how coordinate changes might influence their workflows. For example, it can help determine how the shifts in coordinates will affect agricultural activities such as planting, fertilizing and harvesting. Will farmers need to remap their fields, or will a transformation be sufficient?

    Fostering collaboration with stakeholders and constituents will help users better understand how the NSRS modernization impacts their products and services. Developing strategies to align geospatial data management with regulatory requirements and operational objectives will also facilitate a smoother implementation process. NGS is partnering with federal agencies and professional societies to create a self-assessment guide that helps organizations evaluate how the NSRS update affects their geospatial missions. As previously mentioned, the North Carolina 2022 Reference Frame Working Group is working with state and local agencies, as well as surveyors, to proactively address key questions and challenges. This collaboration aims to improve communication with NGS and determine whether their products and services need to be reprocessed, re-surveyed or transformed to suit the new standards.

    Each organization has its own unique geospatial requirements and a thorough understanding of its mission and needs. This is an ideal opportunity to develop a centralized plan for evaluating and managing geospatial workflows during the transition to the modernized NSRS. Challenges include aligning legacy datasets with new reference standards while ensuring data integrity. Organizations should assess the accuracy of their data in relation to the NSRS and document any necessary updates in metadata. By creating a well-structured plan that balances operational constraints, legal compliance and practical considerations, organizations can prioritize accuracy, efficiency and alignment with the updated NSRS.

    To assist others in preparing for the new NSRS, Dana J. Caccamise II, NGS regional geodetic advisor, has developed guidance materials that have been shared with federal agencies — including the FGDC and their team leaders — and professional organizations such as NSPS, ASPRS and AAGS. See the boxes titled “Questions to Guide a Self-Assessment of Your Operation and Products” and “List of NGS Products and Services — Are your workflows dependent on one or more NGS products.” The goal is to help these agencies become ready to implement the new NSRS once it is officially adopted by NGS.

    Questions to Guide a Self-Assessment of Your Operation and Products
    Are you generating or using geospatial data (or doing both)?
    – If so, your workflows are likely dependent on geodetic control tied to one or more NGS products. The upcoming NSRS update will affect these dependencies. (See “List of NGS Products and Services.”)
    Do you know if your mission, project, or datasets depend on NGS products?
    – Identifying whether and how your entity relies on NGS products is a critical first step in assessing potential impacts.
    What are your accuracy, precision, and shelf-life requirements for geospatial data?
    – Understanding your mission’s specific data requirements ensures you can evaluate whether NSRS modernization will meet your operational needs without unnecessary adjustments. This should include plans to accommodate greater accuracy in the future.
    Do you know how your entity accesses and utilizes geospatial data?
    – Are you obtaining it directly from NGS or indirectly through third-party vendors (e.g., RTN systems, GIS platforms, GNSS companies)?
    – Have you considered how updates to NGS products may impact the tools or services you rely on from these vendors?
    – Many entities rely on geodetic control without realizing it. NGS’s foundational data and frameworks are often invisible and seamlessly embedded within the tools and services offered by third-party vendors, such as GIS platforms, survey equipment, and software providers. These vendors, in turn, depend heavily on NGS products like the NSRS to ensure their tools are accurate and functional. Understanding this indirect reliance is crucial for preparing your workflows and ensuring continuity as the NSRS is modernized.
    Where does your entity fit in with the geodetic workflow?
    – Does your entity create integral products (e.g., GNSS data, lidar data) on which other products depend?
    – Does it produce derivative products (e.g., DTM, Topographic Map, Flood Insurance Rate Map (FIRM) and Flood Insurance Study (FIS) Report)?
    – Evaluating these dependencies will help you determine the scope of NSRS modernization impacts.
    What are your project requirements for data accuracy and longevity?
    – Assess whether your data accuracy thresholds and long-term usability align with the modernized NSRS.
    Have you evaluated workflows and identified potential impacts in areas affected by significant ground movement (e.g., regions with tectonic shifts, vertical land motion, and, most notably, subsidence)
    – Identifying potential risk or disruption areas can guide prioritization and help mitigate impacts on critical operations.

    List of NGS Products and Services

    Are your workflows dependent on one or more NGS products

    Products and ServicesExamples
    Geodetic Control Data– Datasheets
    – State Plane CoordinatesSurvey
    – MarksSurvey Data
    National Spatial Reference System (NSRS) Datasets– Horizontal (Geometric) reference frames
    – Vertical (Orthometric / Physical) datums
    – Geoid Models
    NSRS Tools and ResourcesNGS Geodetic Tool Kit
    – NGS PC Software such as ADJUST
    – User-Contributed Software
    – VDatum to convert elevation data
    – Other NSRS Resources such as transformation tools
    GNSS Data and SolutionsOPUS (Online Positioning User Service)
    – CORS (Continuously Operating Reference Stations)
    – Satellite Orbits
    Gravity Data– Gravity for the Redefinition of the American Vertical Datum (GRAV-D)
    – Deflection of the Vertical (DoV)
    Coastal Mapping Products– Topobathy lidar Data
    – Shoreline Mapping Products
    Aerial Imagery and Remote Sensing– NOAA Remote Sensing Division Products such as Emergency response imagery (e.g., hurricane damage)
    Analytical tools– Least squares analysis tool
    – Antenna Calibrations
    GIS and Visualization Tools– Geospatial Data such as Shapefiles and KML files for GIS applications
    – Web Services
    Educational and Reference Materials– Documentation such as NGS technical reports
    – Presentations and Posters
    – User support such as NGS Information Center and Regional Geodetic advisors
    Historical Data Archives– Legacy Products such as Older geodetic survey records and Superseded geoid models and transformation tools
    Standards and Procedures, best practices, data formats– Standards and Procedures such as NOAA Technical Memorandum NOS NGS 92
    – Data Formats such as GVX (Real-time or post-processed GNSS vectors)

    To support the increased awareness of the modernization of the NSRS, under the auspices of the Federal Geodetic Control Subcommittee, NGS will host a meeting with federal geospatial agencies on Oct. 15, 2025, to discuss the NSRS modernization. The primary objectives of this meeting are to:

    • Increase awareness of the NSRS modernization rollout schedule and engagement strategy, including self-assessment and interaction between official departmental working groups.
    • Within other departments, connect decision-makers to those who accomplish NSRS modernization tasks and designate points of contact to interface with NGS capacity building efforts.
    • Share experiences and strategies among federal agencies concerning NSRS modernization self-assessment and preparation.
    • Gather questions, discuss anticipated challenges and identify opportunities to support each other through this transition.

    It is my understanding that this meeting is open to the public (virtually) for listening and observation. See below for more information on the meeting.

    Federal Geodetic Control Subcommittee Meeting

    • Date: Wednesday, October 15, 2025
    • Time: 1:00 PM – 4:00 PM ET
    Photo:

    I recommend that NSRS users consult guidance from NGS and engage with professional societies that have established working groups to analyze the impact of the new NSRS on geospatial products and services. Getting involved now will help ensure you are prepared when NGS officially adopts the updated NSRS. As Dru Smith, NGS NSRS modernization manager, explained in his webinar titled “NSRS Modernization — Big Steps Forward and What Comes Next” on Aug. 14, 2025, once the initial set of products and services of the modernized NSRS is “official,” the new NSRS becomes “The NSRS,” and its implementation then begins.

    Are you prepared to implement the new NSRS once NGS officially adopts it? Do you have the necessary tools and resources in place to support a smooth transition? This newsletter highlighted several actions that users can take now to ensure they are ready to implement the new NSRS when it becomes official.

  • California updates its spatial reference network

    California updates its spatial reference network

    The California Spatial Reference Center (CSRC) modernized the California Spatial Reference Network (CSRN) on July 31, 2025. The new California Spatial Reference Network is denoted as CSRN Epoch 2025.00. 

    These coordinates changes affect California geospatial users, but the transition process to the new epoch is something that others should understand to prepare for the new, modernized National Spatial Reference System (NSRS), which is expected to be adopted in 2026. As I mentioned in my August 2025 newsletter, NSRS users should proactively assess their geospatial data dependencies and evaluate how adoption of the new datum will affect workflows, datasets and operational decision‑making. 

    The California Spatial Reference System (CSRS) is the official geodetic datum in California, as published by the California Spatial Reference Center (CSRC) according to Public Resources Code (PRC) §§8850–8861. The image below depicts the CSRN. It is rigorously aligned to the current definition of the National Spatial Reference System (NSRS) through a set of coordinate transformations from ITRF2020 to NAD83(2011) as published by the NOAA/NOS National Geodetic Survey (NGS). The California Spatial Reference System (CSRS) is realized by the geodetic coordinates and uncertainties of the CSRN on the date of 2025.00 (January 1, 2025; GPS week 2347, day 3) of 1068 GNSS stations (881 active and 187 defunct stations) in California and at the borders of Arizona, Nevada, Oregon and Baja California. CSRN Epoch 2025.00 NAD83(2011) replaces the previous CSRS Epoch 2017.50 NAD83(2011).

    The latest hybrid geoid model GEOID18 published by NGS was used to compute Global Navigation Satellite System (GNSS)-derived orthometric heights (DCOH) on the North American Vertical Datum of 1988 (NAVD 88) datum in accordance with the California PRC §§8890-8902 (California Orthometric Heights).

    Plot of CSRN (Credit: SOPAC)
    Plot of CSRN (Credit: SOPAC)

    As previously mentioned, the new CSRC Epoch 2025.00 (NAD83 (2011) replaces the previously published CSRC Epoch 2017.5 NAD83 (2011). Readers can obtain the project report that provides technical information about the new realization at the following link: https://sopac-csrc.ucsd.edu/index.php/csrn-epoch-2025-00/ . The website provides web-links to the project report and a table of stations that includes information about the coordinates.  See the image captioned “Excerpt from CSRC Epoch 2025.00 Web Page” for the links to the reports and tables.  The CSRC Epoch 2025.00 realization is aligned with NAD83 2011, Epoch 2010.0.  See the image captioned “Excerpt from Project Report V2” for the summary from the report. I have highlighted some sections of the summary that I thought others would find of interest.

    Excerpt from CSRC Epoch 2025.00 web page.
    Excerpt from CSRC Epoch 2025.00 web page.

    Excerpt from Project Report V2

    Summary

    This report, prepared under California Department of Transportation (Caltrans) Contract No. 52A0157, Task Order 1, documents the modernization of the California Spatial Reference Network (CSRN) by the California Spatial Reference Center (CSRC). This updated realization aligns the CSRN with the North American Datum of 1983 (NAD83 2011, epoch 2010.00).

    The new reference frame, effective on January 1, 2025 (GPS Week 2347, Day 3), is called CSRN Epoch 2025.00 NAD83(2011), referred to for short as CSRN Epoch 2025.00. It replaces the previous adjustment at Epoch 2017.50 and remains a core component of the California Spatial Reference System (CSRS).

    The CSRN is defined by the geodetic coordinates and uncertainties (Table 1) of 1,068 continuous GNSS stations—881 active and 187 inactive or decommissioned—located throughout California and bordering regions in Arizona, Nevada, Oregon, and Baja California, Mexico. As California’s official geodetic reference network under Public Resources Code (PRC) §§8850–8861, all Caltrans surveys using the California Coordinate System of 1983 (CCS83) must reference CSRN control stations or comply with CSRN specifications. The definition and use of CCS83 are governed by PRC §§8801–8819. This new realization is fundamentally tied to the International Terrestrial Reference Frame 2020 (ITRF2020) through the IGb20 coordinates adopted by International GNSS Service (IGS) Analysis Centers. All multi-year processing for this project was performed within this state-of-the-art global reference frame. Furthermore, the CSRN Epoch 2025.00 is rigorously aligned with the National Spatial Reference System (NSRS) maintained by the National Geodetic Survey (NGS). Epoch 2025.00 geodetic coordinates are transformed from ITRF2020 to NAD83(2011) using the NGS Horizontal Time-Dependent (HTDP) utility (Figure 1). The ITRF2020 coordinates (X,Y,Z) of the 1068 CSRN stations are transformed into geodetic coordinates (latitude, longitude and ellipsoidal height), using the GRS80 ellipsoidal parameters (semi-major axis, a = 6378137 m and inverse flattening, 1/f = 298.257 222 101).

    CSRC submitted to the European Petroleum Survey Group (EPSG) definitions for datums, transformations, and coordinate reference systems for Epoch 2025.00 to facilitate unique terminology with associated metadata.

    GPS data (phases and pseudoranges contained in RINEX data files) collected at the CSRN stations from June 10, 1992 to May 17, 2025, and about 300 global tracking stations of the IGS network were re-analyzed in the ITRF2020 reference frame. The complete set of RINEX data and metadata are accessible from the Scripps Orbit and Permanent Array Center data archive.

    The latest hybrid geoid model GEOID18 published by NGS is used to interpolate geoid heights for each of the CSRN stations as the basis of Global Navigation Satellite System (GNSS) derived California Orthometric Heights (DCOH) on the NAVD 88 datum in accordance with the California PRC §§8890-8902 (California Orthometric Heights).

    Figure 1. Reference frames for CSRN Epoch 2025.00 NAD83(2011).
    Figure 1. Reference frames for CSRN Epoch 2025.00 NAD83(2011).

    As provided in the summary of the report, a diagram noted that the ITRF 2020 cartesian (XYZ) coordinates were transformed into NAD83 (2011) cartesian (XYZ) coordinates, and then into local topocentric coordinates (NEU) to obtain the CSRC Epoch 2025.00 NAD83 (2011) coordinates. 

    I downloaded the table of stations with their various coordinates and plotted the differences between the new CSRC Epoch 2025.00 NAD83 (2011) and the previous CSRC Epoch 2017.50 (NAD83 (2011) for stations that were designed as operational stations in 2025.  The following plots depict the difference in coordinates between Epoch 2025.00 and Epoch 2017.50.  One can see that there’s a reason that California needs to periodically update the coordinates of the California Spatial Reference Network.  Some of the horizontal coordinates have changed over 300 mm or around one foot.  The vertical coordinate changes are not as large, but some do shift more than 4 cm.

    Note: The plots do not include newer stations with less than 6 months of solutions (no velocities estimated) and defunct stations (stations in Epoch 2017.50 but no data before January 1, 2025.

    Differences in horizontal coordinates (N, E) between Epoch2025.00 and Epoch 2017.50 northern section.
    Differences in horizontal coordinates (N, E) between Epoch2025.00 and Epoch 2017.50 (northern section).
    Differences in horizontal coordinates (N, E) between Epoch2025.00 and Epoch 2017.50 southern section.
    Differences in horizontal coordinates (N, E) between Epoch2025.00 and Epoch 2017.50 (southern section).
    Differences in vertical coordinates (U) between Epoch2025.00 and Epoch 2017.50 (northern section)
    Differences in vertical coordinates (U) between Epoch2025.00 and Epoch 2017.50 (northern section).
    Differences in Vertical Coordinates (U) between Epoch2025.00 and Epoch 2017.50 (southern section)
    Differences in Vertical Coordinates (U) between Epoch2025.00 and Epoch 2017.50 (southern section)

    The image below provides some statistics about the differences in coordinates between Epoch 2025.00 and Epoch 2017.50.

    Photo:
    Notes: (1) Only includes operational stations in 2025 (2) Does not include newer stations with less than 6 months of solutions (no velocities estimated). (3) Does not include defunct stations: in Epoch 2017.50 but no data before January 1, 2025.

    This newsletter highlighted that the CSRC has adopted a new Public Resources Code–compliant geodetic datum (reference frame) for California: CSRN Epoch 2025.00 NAD83(2011), which replaces CSRN Epoch 2017.50 NAD83(2011). The updated datum incorporates secular (linear) tectonic motions across the North America–Pacific plate boundary, transient motions (such as coseismic and postseismic deformation and fault creep), vertical land motion (subsidence and uplift), and data from new stations established since Epoch 2017.50. Additionally, the new vertical datum provides a comprehensive set of California Orthometric Heights on the NAVD88 datum for all CSRN stations.

    In essence, the CSRC has released three new datums. The first is tied to ITRF2020, the second to NAD83(2011), and the third to NAVD88. Transformation parameters are available between the first two datums. The NAD83(2011)-based datum satisfies California’s Public Resources Code requirements and is the recommended standard for geodetic control in the state. The NAVD88-based datum provides GNSS-derived California Orthometric Heights of 1988 (COH88).

    These new datums will be added to the European Petroleum Survey Group (EPSG) database, the worldwide standard for coordinate reference systems (CRSs) and transformations. Each will receive a unique EPSG code, making it easy to reference and use. This will ensure that CSRN Epoch 2025.00 NAD83(2011), CSRN Epoch 2025.00 (ITRF2020), and COH88 Epoch 2025.00 (NAVD88) can be seamlessly integrated into industry software.

    The CSRC report also noted that NGS has released a beta version of the modernized horizontal and vertical datums for the NSRS: NGS New Datums.

    Once the modernized NSRS is fully published, and in response to the needs of California’s user community, CSRC will continue working to secure resources that support its partnership with NGS and ensure ongoing compatibility with national programs.

  • Inside the new NSRS beta tools and a journey through geodetic history

    Inside the new NSRS beta tools and a journey through geodetic history

    This newsletter is going to highlight some history of the Coast and Geodetic Survey and provide the latest information on the National Geodetic Survey (NGS) new National Spatial Reference System (NSRS). First, every year my brother and I get together and travel to visit friends and relatives. He lives in Montana, and I live in North Carolina, so our yearly trips are typically 10 to 14 days long. As in all trips, I look for geodetic marks along the way. This year we traveled to coastal Maine to visit lighthouses and of course eat lobster rolls. We visited 12 Lighthouses along the Maine Coast. Lighthouses have both historical and navigational importance. The lighthouses were essential in guiding sailors through rocky shores. Portland Head Light commissioned by George Washington in 1791 is Maine’s oldest lighthouse and still guides vessels into Portland Harbor. We found NOS benchmark 841 8031 B 1979 on the grounds of this lighthouse. Pemaquid Point Lighthouse is managed by the Friends of Pemaquid Point Lighthouse, a chapter of the American Lighthouse Foundation, and remains an active aid to navigation under the ownership of the U.S. Coast Guard. We could climb up the Pemaquid Point Lighthouse, so I took a photo of the view from the top.

    Portland Head Light (Credit: Dave Zilkoski)
    Portland Head Light (Credit: Dave Zilkoski)

    One of my brother’s requests was to visit the first place in the continental United States to see the sunrise. However, the location of the first place in the continental United States to witness the sunrise depends on the time of year. As indicated in the box titled “First Places to See the Sunrise in the Continental U.S.” Mars Hill is the first place to witness the sunrise in June.

    Mark located on grounds of Portland Head Light. (Credit: Dave Zilkoski)
    841 8031 B 1979 — Mark located on grounds of Portland Head Light. (Credit: Dave Zilkoski)
    Pemaquid Point Lighthouse (Credit: Dave Zilkoski)
    Pemaquid Point Lighthouse (Credit: Dave Zilkoski)
    View from Pemaquid Point Lighthouse (Credit: Dave Zilkoski)
    View from Pemaquid Point Lighthouse (Credit: Dave Zilkoski)

    First Places to See the Sunrise in the Continental U.S.

    • October 7 to March 6: During these months, Cadillac Mountain in Acadia National Park, Maine, holds the distinction of being the first place in the continental U.S. to see the sunrise. Its elevation of 1,530 feet and eastern location make it ideal for early morning views. reddit.com+10nps.gov+10acadiamagic.com+10
    • March 25 to September 18: In the spring and summer, Mars Hill in Aroostook County, Maine, takes the title. Its northeastern position allows it to catch the first rays of sunlight during this period. newengland.com+2en.wikipedia.org+2aa.usno.navy.mil+2

    Around the Equinoxes: Approximately during the weeks surrounding the spring and fall equinoxes, West Quoddy Head in Lubec, Maine—the easternmost point of the contiguous U.S.—experiences the nation’s first sunrise. reddit.com+2en.wikipedia.org+2en.wikipedia.org+2

    That said, when we travel together, we always recover geodetic marks, so we chose to visit Cadillac Mountain even though in June the first place is located on Mars Hill in Aroostook County.  

    As many of you know, I worked for NGS for 35 years so reconning monuments is exciting to me. We found six marks in a radius of about two hundred meters on Cadillac Mountain. We will talk about them in a minute.

    Cadillac Mountain was important to me because from 1833 to 1898, the Coast and Geodetic Survey performed a triangulation project that extended from Calias, Maine, to New Orleans, Louisiana. The project was published as the Eastern Oblique Arc of the United States. The station Mount Desert 1856 that was located on Cadillac Mountain was part of this project. A report published in 1902 describes the Eastern Oblique Arc project and can be downloaded here.

    USCGS Special Publication Number 7. (Credit: USGS)
    USCGS Special Publication Number 7. (Credit: USGS)

    According to the 1902 report, horizontal observations at station Mount Desert 1856 were acquired by Alexander Dallas Bache. That may not mean much to most people, but Mr. Bache was the second superintendent of the Coast Survey and was particularly important to the advancement of geodesy in the United States. As a side note, the Coast Survey was renamed the Coast and Geodetic Survey in 1878. The change reflected the agency’s expanded mission beyond coastal charting to include geodetic surveys of the nation’s interior, prompted by the growing importance of geodesy in its work.

    Bache’s leadership of the U.S. Coast Survey

    In 1843, Bache was appointed superintendent of the United States Coast Survey, succeeding Ferdinand Rudolph Hassler. Under his leadership, the Coast Survey expanded its missions to include hydrography, geodesy, topography, and the printing arts. He initiated geomagnetic studies, directed tide observers to make meteorological observations, and developed mathematical techniques for tide predictions and adjusting triangulation networks. Bache’s administrative skills transformed the Coast Survey into one of the foremost scientific organizations globally, providing critical data for navigation and commerce.

    Alexander Dallas Bache.
    Alexander Dallas Bache

    According to the description of Mount Desert in the 1902 USCGS report, the station was marked by a copper bolt in a ledge (see the box titled “1856 Description of Mount Desert”). The 1902 description of the station on the NGS Datasheet stated that it was a hole drilled in a rock (see the box titled “1902 Description of Mount Desert”). I’m not sure why there is a discrepancy between the two descriptions but in 1931 the Maine Geodetic Survey found the drill hole, and based on measured references to other drill holes in the area that were documented in the original description decided that it was the location of the original station (see the box titled “1931 Description of Mount Desert”).  At that time, a Coast and Geodetic Survey Disk with Reference Marks were installed by the Maine Geodetic Survey.

    A description of Mount Desert from 1856. (Photo: NGS)
    A description of Mount Desert from 1856. (Photo: NGS)
    A Description of Mount Desert from 1902
    A description of Mount Desert from 1902.
    A description of Mount Desert from 1931.
    A description of Mount Desert from 1931.
    A description of Mount Desert from 1931.
    A description of Mount Desert from 1931.

    As I previously stated, we found six marks in the area. The boxes titled “Photos of Mount Desert 1856 and Reference Marks” and “Photos of Other Marks on Cadillac Mountain” provide photos of the monuments we found on Cadillac Mountain.  One may note that the reference mark 2 monument is in worse shape than the reference mark 1 and the Mount Desert monument. The 1944 recovery note stated that reference mark 2 was covered with roadway stone. There was not any stone covering reference mark 2 when I found it. Reference mark 1 is located behind some trees and out of sight of the path.

    When I arrived at the site, there were a group of people looking at reference mark 2. I held a little lecture on the importance of geodetic monuments and how this site was first occupied in 1856; and, of course, I highlighted the importance of geodesy.

    Photos of Mount Desert 1856 and reference marks. (Credit: Dave Zilkoski)
    Photos of Mount Desert 1856 and reference marks. (Credit: Dave Zilkoski)

    I was thrilled to stand in the very spot where Alexander Dallas Bache took geodetic measurements in 1856. [I know—people joke that I need to get a life, all because I get so fired up over geodetic monuments.]

    The box titled “Abstract of Observations at Mount Desert” provides a summary of the directions from Mount Desert to the stations involved in this phase of the project. The box also includes a photo of an instrument, a 75 cm theodolite, which was used to perform the observations. The box titled “Diagram of Network Depicting Epping Base Line” provides a diagram that was included in the 1902 USCGS report.

    As a side note: during the 1970s as a NGS employee, I personally coded abstracts similar to this one to convert archival data into computer-readable form in support of the North American Datum of 1983 (NAD83) project. Once all data were in computer-readable form, they were reviewed for correctness and combined in an adjustment resulting in what is known as NAD 83 (1986).  See the NGS report for some details of the NAD 83 (1986) here.

    Abstract of Observations at Mount Desert (Credit: NGS)
    Abstract of Observations at Mount Desert (Credit: NGS)
    Diagram of network depicting Epping Base Line. (Credit: NGS)
    Diagram of network depicting Epping Base Line. (Credit: NGS)

    The other marks we found on Cadillac Mountain included a US Geological Survey Benchmark – K 24 1934, a bent pipe denoted as Cadillac Ground, and a Department of Interior Geological Mark – Cadillac 1975. All these marks are within a 200-meter radius of each other. My understanding is that Cadillac Ground was established because Mount Desert was obstructed by trees. I have provided weblinks for those that would like more information on these marks.

    Photos of other marks on Cadillac Mountain. From left to right, K 24 1934, Cadillac Ground and Cadillac 1975. (Credit: Dave Zilkoski)
    Photos of other marks on Cadillac Mountain. From left to right, K 24 1934, Cadillac Ground and Cadillac 1975. (Credit: Dave Zilkoski)

    After visiting more lighthouses along the Maine Coast, we traveled back to Boston and visited Waldon Pond and Thoreau’s family home. Why Thoreau you ask? In 2018, the Surveyors Historical Society and NSPS Foundation recognized Thoreau for his work as a surveyor by establishing a commemorative monument at Thoreau’s family farm.

    Thoreau described surveying as a “noble employment” that kept him close to nature: “Surveying … brings you within hearing of [the birds]” – https://www.heritagesurveys.com/famous-surveyors. Surveying and geodesy are indeed noble professions; they provide the foundation for all geospatial products and services.

    Photo of Commemorative Mark at Thoreau’s House. From left to right, Thoreau – A Surveyor, Thoreau Monument and drawing lines. (Credit: Dave Zilkoski)
    Photo of Commemorative Mark at Thoreau’s House. From left to right, Thoreau – A Surveyor, Thoreau Monument and drawing lines. (Credit: Dave Zilkoski)

    Finally, we left Boston for Syracuse to visit my younger brother and sister. I attended the SUNY College of Environmental Science and Forestry (SUNY ESF) which is immediately adjacent to Syracuse University campus. Both of my brothers attended Syracuse University, so we like to walk around campus whenever we visit Syracuse. During our trip to the University, we recovered the monument Thornden 1934. Thornden 1934 was significant to me because I recovered this monument over 50 years ago, as part of a special project that I performed for my geodesy class.

    Thornden 1934 (Credit: Dave Zilkoski)
    Thornden 1934 (Credit: Dave Zilkoski)

    I hope this was not too boring for you, but I real enjoy history and especially the history of the geodetic network of the United States. Today, you can use modern surveying technology to obtain a more accurate coordinate in seconds where it took days to months in the past. That is amazing!

    Now, what is the latest with the modernization of the National Spatial Reference System? On June 17, NGS announced that they incorporated four groups of NSRS modernization products to the NGS beta website.

    Multiple NSRS Modernization Products Published to Beta

    NGS has released the following four groups of products to the NGS beta website to solicit review and feedback from stakeholders as part of the modernization of the National Spatial Reference System (NSRS): (Note: These products are not final and should not be used for anything other than review and testing.)

    North American-Pacific Geopotential Datum of 2022 (NAPGD2022). This datum will replace the North American Vertical Datum of 1988 (NAVD 88) and all other vertical datums for islands in the United States. It will serve as a foundational component of the modernized National Spatial Reference System (NSRS), providing precise definitions for orthometric height (elevation). The release includes the defining grids that collectively make up the datum along with a number of supporting products to visualize the datum.

    Products. All NAPGD2022 products are provided as grids for the following: GEOID2022, DEFLEC2022, GRAV2022.

    Example coordinates. Coordinates and product values are computed for numerous example points throughout NAPGD2022 and provided in a table. NAPGD2022 Experience. Interactive online maps showing NAPGD2022 products for all regions that can be used on a computer or mobile device to query any location.

    Maps of NAPGD2022 products. Static map images of NAPGD2022 products for all regions.New Terrestrial Reference Frames of 2022 for North America (NATRF2022), Pacific (PATRF2022), Caribbean (CATRF2022), and Mariana (MATRF2022) plates. These four geodetic reference frames will replace the North American Datum of 1983 (NAD 83). They will serve as a foundational component of the modernized NSRS, providing precise definitions for geodetic latitude, longitude, and ellipsoidal height.

    Euler Pole Parameters of 2022. All of the new terrestrial reference frames are defined by transformation from the International Terrestrial Reference Frame of 2020 (ITRF2020) using Euler Pole Parameters (EPPs) that model tectonic plate rotation.

    State Plane Coordinate System of 2022 (SPCS2022). A system of map projections for accessing the modernized NSRS. Zone designs have been incorporated into the following beta products and services:

    Zone information tables. SPCS2022 zone definitions, example coordinate computation results, minimum and maximum coordinate values, and minimum coordinate differences with overlapping SPCS2022 zones and with other coordinate systems, provided as interactive tables that can be sorted and filtered.

    SPCS2022 Experience. Interactive online maps showing distortion for all SPCS2022 zones that can be used on a computer or mobile device to get distortion at any location or to view zone definitions.

    Maps of SPCS2022 zones and distortion. Static map images of SPCS2022 zone layers, number of zones, and distortion with performance statistics.

    NGS Coordinate Conversion and Transformation Tool (NCAT). This version can be used to perform SPCS2022 coordinate conversions at any location for all SPCS2022 zones. Later beta versions will include the ability to transform between reference frames and vertical datums.

    Products found on the NGS beta website are preliminary releases that are for testing and evaluation only; they are not final products nor do they contain any authoritative NGS data or tools. To provide feedback on any of the content on this site, please email [email protected].

    Everyone should review these products and provide their feedback to NGS. That said, my April 2025 newsletter highlighted the NAPGD2022 Alpha product that was moved to the Beta site. The Beta product is like the Alpha product, but it does not have an option for an interactive computation. The Interactive Computation Option provided essential information about NAPGD2022 and would be helpful to geospatial users for obtaining a better understanding of the differences between NADGP2022 orthometric heights and NAVD 88, and GEOID2022 geoid heights and hybrid GEOID18 geoid heights. My April 2025 newsletter highlighted the interactive computation option.

    Alpha interactive computation page (Credit: NGS)
    Alpha interactive computation page (Credit: NGS)
    Alpha interactive computation page (Credit: NGS)

    As noted in my April 2025 newsletter, I downloaded the data and created my own maps to better highlight local variations. Although users can still view the original via the interactive online map, this personalized version offers clearer insights.

    Here are several of my comments on the Beta products based on my preliminary review:

    • The NAPGD2022 difference map (NAPGD2022 minus Historical in meters) uses 25 cm intervals, which are too coarse to reveal the finer local variations between published benchmarks accurately.
    • The NAPGD2022 Difference map should have an overlay of the marks used in the creation of the difference map. This would allow users to identify marks in their region of interest. Clicking on a mark should link to the NGS datasheet and Passive Mark Page.
    • The beta page for NATRF2022, PATRF2022, CATRF2022, and MATRF2022 is not particularly helpful for everyday geospatial users. There should be an Interactive Computation Option to enter NAD83 (2011), epoch 2010 coordinates where the routine transforms the coordinates into ITRF 2020, epoch 2020, as well as estimates in the new terrestrial reference frames – NATRF2022, CATRF2022, PATRF2022, and MATR2022.
    • Both the State Plane Coordinate System of 2022 (SPCS2022) and The NGS Coordinate Conversion and Transformation Tool (NCAT) are good tools for users to obtain an understanding of the differences and changes in the SPCS especially for their State. That said, like above, there should be an option to enter NAD83 (2011), epoch 2010 coordinates where the routine will transform the coordinates into ITRF 2020, epoch 2020, as well as estimates in the new terrestrial reference frames – NATRF2022, CATRF2022, PATRF2022, and MATR2022. The routine does have a note that states users can transform their coordinates using HTDP, but NGS should incorporate this process in the NCAT beta product.
      • Note from Beta NCAT product: This beta version of NCAT supports beta State Plane Coordinate System of 2022 (SPCS2022) but not transformations between reference frames or geopotential datums. NAD 83 latitude and longitude can be used as input, but the output coordinates will differ horizontally from actual SPCS2022 by up to a few meters, depending on location (likewise for UTM and USNG). If NAD 83 ellipsoid heights are used, the linear distortion and combined factor will differ from SPCS2022 values by a small amount, within ±0.3 parts per million (ppm). To reduce these differences, NAD83 epoch 2010.0 coordinates can first be transformed to ITRF2020 epoch 2020.0 using the Horizontal Time-Dependent Positioning (HTDP) tool.

    I plan to provide these comments to NGS through their feedback email process. Everyone should take time to review these products and provide your feedback to NGS. Remember, NGS placed these four groups of products on the NGS beta website to solicit review and feedback from stakeholders as part of the modernization of the National Spatial Reference System (NSRS) process. Users should review these Beta products and consider two questions:

    1. Do these products provide sufficient information and detail for documenting how I will deliver my products and services under the new NSRS?

    2. Do I need additional information or tools from the NGS to better understand the changes and impacts of the new NSRS?

    Your feedback will help NGS improve the Beta products.

  • GeoGov 2024 Summit addresses benefits, challenges and opportunities of new, modernized NSRS

    GeoGov 2024 Summit addresses benefits, challenges and opportunities of new, modernized NSRS

    On Sept. 10, the GeoGov 2024 Summit hosted a panel discussion between NGS and other federal and industry leaders on the modernized National Spatial Reference System (NSRS). High-level management and leadership officials attended the conference, which was a great place to network and collaborate with federal agencies.

    Photo:
    Panel session on NSRS modernization.

    As you can see from the announcement, the panel members represented a wide range of users of the NSRS.  They were asked to address the following four topics based on their perspective of the rollout of the new, modernized National Spatial Reference System:

    1. Benefits of Modernization
    2. Challenges of Modernization
    3. Opportunities Provided by Modernization
    4. Next Steps in Collaboration

    As one would expect, there was a wide range of responses based on the individual panel’s perspective of what the new, modernized NSRS means to their products, services and constituents. Even though there were many responses based on the individual panel’s perspective, there were many common ideas. This newsletter will highlight some of the bullet points presented by the panel members during their presentations. I attempted to combine similar statements for every topic under a common theme.

    Summary of Benefits of Modernization

    • A unified four-dimensional system will finally provide a sustainable spatial reference frame for managing the state’s geospatial resources.
      • Combining of horizontal and vertical datums in one system
      • Improved spatial data quality – both horizontal and vertical
      • Simplification in which vertical reference frame and GEOID to use in local areas with the new NAPGD2022
      • Improved accuracy of the horizontal and vertical coordinates
      • A common “language” or framework for spatial data
      • Greater consistency in non-CONUS areas like AK, Hawaii, PR, and USVI
    • We can write NSRS requirements into any task order for acquisition
      • Additional uniformity for surveying practitioners
      • Better spatial data sustainability
    • The unification of marine and terrestrial geoids is important for managing our valuable coastal resources (all heights should be geoid based)
      • Closer integration with tidal datum information
      • Improved height information will enable us to provide the most accurate data possible
    • Direct relationship to ITRF2020 offers the ability to deliver the intra-frame deformation model through real-time networks
      • The introduction of reference epochs on NGS geodetic survey benchmarks and the time-dependency of the datums
      • The ability to more easily link the data to ITRF
    • Expansion of low distortion projection (LDP) systems
    • Lack of metadata within historical information to adapt to the new datum
      • Ensuring data fidelity, now and always! (METADATA)
    • People and processes; not technology
      • Users with lack of understanding of a time-dependent datum
      • Surveyor making time to learn about new datum
      • Understanding the impact of the new system to your products and services
    • How do we convince them to effectively transition all their historic data to the latest reference system?
      • Confusion among end users in understanding geodetic terminology and time-dependent way of perceiving coordinates
      • Adequate understanding by all stakeholders
    • Degrading coordinates and heights can impact reliability over project lifespans (NGS may not be able to respond to natural changes and emergencies)
      • Maintaining an accurate deformation model for use by many geospatial users in their specific workflows
    • Updating specifications on ground surveys for lidar and ortho projects that are processed through OPUS (How do we better educate our team and partners on what can be considered accurate for those observations)
      • Updating of existing surveying equipment to include new datum
      • Potential confusion in reported accuracy as it relates to changes in epoch vs. actual error of the equipment (ground-based or aerial/satellite) and the approach used to measure the feature
    • Transformations to new datums may incur costs if partners do not want to “modernize” data (Potential of needing two copies of data delivered)
      • Will need to develop policy deciding if we “modernize” all our older/existing data, or just start with the new NSRS at a certain point in time
      • Need operational software that reprojects/transforms data – especially large, bulk features (e.g., lidar point clouds)
    • Combining legacy data with modern data can lead to loss of data fidelity and often difficult to recognize changes to the data

    Many challenges were mentioned, but I found it interesting that panel members highlighted issues with the user’s lack of understanding of the new system’s impact on their products and services.  It is about people, not the processes or new technology.  This was not surprising to me because this was an issue when NGS implemented the North American Vertical Datum of 1988 (NAVD 88).  I know this firsthand because I was the NAVD 88 Program Manager while working for NGS.  Surveyors and mappers are used to dealing with new technology and datum changes. Still, management and leadership have different issues that need to be addressed for new technology and datum changes.  Hopefully, the management and leadership that attended the GeoGov 2024 Summit will start identifying how their products and services will be affected by the new NSRS and developing implementation plans.

    Summary of Opportunities Provided by Modernization

    • Increased collaboration between private entitles and public agencies
      • Providing better service
      • Reducing cost
      • Improving safety and welfare
      • Expanding innovation
      • More reliable data for monitoring trends in infrastructure
      • Providing efficient and cost-effective tools and processes for users to update their mapping products to the new reference system
    • More accurate data collection/dissemination to benefit the public
      • More uniformity of data collection between surveyors
      • Improved reliability of advanced positioning built on the new NSRS
      • Improved heights for flood mapping products for forecasting, infrastructure planning and design, and accessibility using GNSS
      • Facilitates integration of tidal datum, critical to coastal science and industry
      • Allows for unification with SAR imagery and satellite altimetry, improving earth observations and mapping products
    • Improved Change Detection estimations
      • Better metadata descriptions for understanding times of collections
      • Increased vertical data for monitoring existing conditions
      • More accurate representation of the Earth’s surface over time as it lates to coastal change (sea level rise, flood modeling, coastal erosion, etc.)
    • Compensating for workforce attrition

    As in any new paradigm, there are opportunities for increased collaboration between users and the development of new products and services. The panel members highlighted opportunities to provide better service to customers, develop more efficient and cost-effective tools for users and improve coastal change detection models. 

    Next Steps in Collaboration

    • Cross promotion of new datums within likeminded professions
      • Recruitment into geospatial professions
      • Increased awareness of the importance of the geospatial professions
      • New or expanded collaborations across professions
      • Leveraging non-federal resources and their active user communities spanning surveying, geophysical science, regional governmental agencies, industry, and academics
      • Working together to convince state/local agencies to adopt the new datums
    • Working with geospatial societies (NSPS, AAGS, ASPRS, URISA,etc.) for impact awareness
      • Working together to identify the new NSRS impact on your products and services
      • Guidance from professional organizations and societies
    • Implementation of tools and processes for datum conversion for large remotely-sense datasets for more effective data analysis for reporting climate change

    Under the next steps in the collaboration section, promoting the new reference frames with other geospatial professionals was mentioned as an opportunity to leverage resources and expand the understanding of the new NSRS’s effect on users’ products and services. That is, increasing the number and types of stakeholders and constituents affected by the new reference frames will increase awareness of the new NSRS.

    Joint Actions to Promote a Smooth Transition

    For a smooth transition of the new NSRS, it is important to identify actions required for implementation.  Promoting awareness to leadership is critical for the implementation of any new system.  In the case of the new NSRS, it is essential for federal agencies to get engaged in the process now.  I was pleased to hear that panel members mentioned that it is vital for federal agency engagement through the Federal Geographic Data Committee (FGDC) and the Federal Geodetic Control Subcommittee (FGCS) to be compliant with the Geospatial Data Act of 2018 (GDA 2018).  These federal agencies must develop plans and allocate resources to implement the new NSRS.

    As previously stated, high-level management and leadership attend the GeoGov 2024 Summit conference. It is a great place for networking and collaborating within federal agencies and for better understanding the issues associated with implementing the new, modernized NSRS. 

    Technology and tools are essential for the development of the new, modernized NSRS.  That said, understanding how the use of technology and tools meet the users’ requirements is necessary for implementation. 

    Some users trust NGS models and tools without following the appropriate procedures.  Standard operating procedures are used in a workflow to help meet users’ project requirements. In my opinion, understanding the impact of the new system on a specific product and service is the most important part of implementing the new NSRS.  Documenting the workflow used to create a product and service and then using this information to develop standard operating procedures that use the appropriate tools and procedures will help implement the new, modernized NSRS.

    In less than a year, NGS will be finalizing the new terrestrial reference frames and geopotential datum.  Time really is running out and users need to obtain a working knowledge of the new, modernized NSRS. 

    NGS publicly given presentations collected for public viewing can be downloaded here.

  • Scripps Institution of Oceanography establishes a geodesy program

    Scripps Institution of Oceanography establishes a geodesy program

    In my November 2023 GPS World newsletter, I highlighted the announcement made by the National Geodetic Survey (NGS) of the recipients of the NOAA FY 23 Geospatial Modeling Competition Awards. The grantees’ proposals include developing models to address what NGS denotes as the Intra-Frame Deformation Model (IFDM). The primary objectives of these projects are to modernize geodetic tools and models, as well as to develop a geodetic workforce for the future. A significant improvement in the new, modernized National Spatial Reference System (NSRS) is the time-dependent component being incorporated in the computation of reference epoch coordinates (RECs). That said, developing models that accurately capture the time-dependent component is extremely important to providing reliable, consistent, and accurate RECs. My February 2024 newsletter highlighted NGS’s grant to The Ohio State University for developing a fully kinematic reference frame for the Continental United States and Canada. Similar to the OSU project, a goal of the Scripps Institution of Oceanography (SIO) project is to provide an accurate IFDM, which will provide reliable, consistent and accurate RECs. On Jan. 10, 2024, Yehuda Bock, Ph.D., gave a presentation about this at the general membership meeting of the American Association for Geodetic Surveying (AAGS). His presentation can be downloaded from the AAGS’s website: https://aagsmo.org/.

    Summary of the SIO Geospatial Award. (Image: NGS website)
    Summary of the SIO Geospatial Award. (Image: NGS website)

    Bock is director of the California Spatial Reference Center (CSRC), which is responsible for “establishing and maintaining an accurate state-of-the-art network of GPS control stations for a reliable spatial reference system in California.” I highlighted the CSRC in my June 2023 GPS World Newsletter.

    Yehuda’s proposal included the following three activities:

    • Create a formal Geodesy Program at SIO to address the nationwide deficiency of geodesists. Expand current geophysics curriculum – funding for five graduate students.
    • Develop an IFDM to supplement the NSRS for users in regions with significant ground motions, using GNSS and InSAR/GNSS displacement fields (funded by NASA projects) and underlying geophysical models. CSRC will exercise the IFDM through its community of public, private and academic users of precise spatial referencing in our challenging region of secular and transient crustal movements.
    • Investigate a unified vertical reference frame, including a marine geoid optimized to be consistent with the full spectrum of observations from modern gravimetric geoids (e.g., GRAV-D, ICGEM), remotely sensed observations (e.g., SWOT, ICESat-2), in situ ocean observations and assimilating ocean models and the TRF.

    Yehuda’s project includes creating a formal geodesy program at SIO that will help to address the geodesy crisis. Anyone keeping up with my columns knows that I have been highlighting the geodesy crisis and programs that advance the science of geodesy (July 2020, November 2022, and December 2022).

    Yehuda showed a slide that highlighted “What Geodesy Can Tell Us About Earth.”  Looking at the slide, geodesists are needed in the field of climatology, meteorology, hydrology, geology, volcanology, oceanography, and glaciology, as well as surveying, mapping, and navigation. All these disciplines study Earth’s dynamic processes and involve geodesy.

    From Dr. Yehuda Bock Presentation to the AAGS General Membership Meeting. (Image: AAGS website)
    From Yehuda Bock Ph.D.’s presentation to the AAGS General Membership Meeting. (Image: AAGS website)

    The images “Geodesy Curriculum at SIO (PhD, MSc)”, “Geodesy Courses – 1” and “Geodesy Courses – 2” provide information about the Geodesy Program as SIO.

    From Dr. Yehuda Bock Presentation to the AAGS General Membership Meeting. (Image: AAGS website)
    From Yehuda Bock, Ph.D.’s Presentation to the AAGS General Membership Meeting. (Image: AAGS website)

    Notice that some of the courses focus on topics that are important to real world applications. For example, GNSS precise point positioning applications to seismotectonics, GNSS signal propagation applications to atmospheric remote sensing and GNSS reflection: soil moisture and sea level and the vertical datum.

    From Dr. Yehuda Bock Presentation to the AAGS General Membership Meeting (Image: AAGS website)
    From Dr. Yehuda Bock Ph.D.’s presentation to the AAGS General Membership Meeting. (Image: AAGS website)

    PhotoFrom Dr. Yehuda Bock Presentation to the AAGS General Membership Meeting (Image: AAGS website)
    FromYehuda Bock, Ph.D.’s presentation to the AAGS General Membership Meeting. (Image: AAGS website)

    In addition to the graduate-level courses, they are proposing an undergraduate course titled Geodesy and Geospatial Information. The purpose of the course is to provide students with the skills in geospatial systems that will provide opportunities for eventual employment in the public and private sectors.

    Proposed Undergraduate Course

     Title: Geodesy and Geospatial Information

    Course justification and content objectives: Geodesy is the study of Earth’s size (geometry), shape (gravity field) and deformations (e.g., plate tectonic motions, subsidence). It provides access to a well-defined spatial reference system for precise geospatial information (latitude, longitude, height, elevation with respect to sea level) used for positioning, navigation, surveying and mapping. Geodesy is also an important discipline within the earth, atmospheric and oceanographic sciences, using observations of GPS and other satellite navigation constellations, remote sensing platforms (satellite and drone), and various terrestrial sensors. It is a data- and analysis-intensive discipline increasingly requiring modern data science methods. This introductory course will provide students with a solid background in geospatial systems for eventual employment in the public and private sectors. The course will also serve as a pipeline to the geodesy track at SIO/Earth Sciences and to other academic institutions and to alleviate the nationwide deficiency of geodesists. The objective is to provide basic knowledge of geodetic concepts for Earth and data scientists and the underlying geodetic framework for precise spatial information.

    Learning objectives:

    • Acquire basis concepts of geodetic science.
    • Provide overview of geodetic instrumentation and observations.
    • Develop elementary skills in geodetic data analysis.
    • Explore existing geodetic infrastructure and data repositories.
    • Experience hands on visualization and manipulation of geospatial information.
    • Understand the underlying geodetic framework for precise spatial information systems.
    • Provide example of data science applications in solving geodetic problems.

    Preferred background: statistics, linear algebra, Matlab/Python

    In my opinion, universities should provide a general elective course for undergraduate students that provides an introduction in how geodesy influences your daily routines. For example, how does my phone know where I am and how does it know the best route I should take to get to my destination?

    How Does My Phone Know Where I Am? (Image: Dave Zilkoski)
    How Does My Phone Know Where I Am? (Image: Dave Zilkoski)

    The second task in the SIO proposal is to develop an IFDM. The concept of an IFDM is part of NGS’ modernized, NSRS. Several of my previous My July 2023 GPS World newsletter highlighted a presentation by Yehuda discussing a kinematic datum that uses an intra-frame velocity model to estimate positions at any time with respect to a reference frame and epoch.

    As I mentioned in my July 2023 newsletter, California’s geodetic network is significantly affected by crustal movement. To help address this issue, the CSRS updated the NAD 83 coordinates, it is denoted as CSRS epoch 2017.5 (NAD 83). Part of the implementation of the CSRC epoch 2017.50 (NAD 83) was to have the new epoch-date coordinates transmitted with RTCM 3.0 data streams. This is something that other RTN operators from around the nation will have to do after NGS publishes the NSRS coordinates. The CSRS is a model from which others can learn.

    During his presentation to AAGS, Yehuda highlighted his methodology of integrating InSAR and GNSS to develop an IFDM that provides for higher spatial resolution to improve the model between GNSS stations.

    The boxes titled “SCIP Dynamic Datum Utility” and “Output from SCIP Utility” provide an example of an input and output of the utility, and the box titled InSAR/GNSS Integration for Higher Spatial Resolution” is a conceptual diagram of the concept.

    Not only has this abbreviation been spelled out before, but here the full phrase appears three times, in three consecutive sentences.

    SCIP Dynamic Datum Utility. (Image: SOPAC website)
    SCIP Dynamic Datum Utility. (Image: SOPAC website)

    Output from SCIP Utility. (Image: (SOPAC Website)
    Output from SCIP Utility. (Image: (SOPAC Website)

    From Yehuda Bock Ph.D.'s Presentation to the AAGS General Membership Meeting (Image: AAGS website)
    From Yehuda Bock Ph.D.’s Presentation to the AAGS General Membership Meeting
    (Image: AAGS website)

    The image provides an example of the concept in the San Joaquin Valley, California.

    InSAR/GNSS Integration Example.
    InSAR/GNSS Integration Example.

    The following statement is in the note section of the slide:

    “Area of subsidence in San Joaquin Valley. Our weekly displacement time series at GNSS station P056 shows significant changes in subsidence rate over the period 2006 to 2022, for a total of 3.3 feet that reflects periods of drought and increased groundwater use. On the upper right is the InSAR time series at that location for a shorter period of time.”  This shows the potential of using InSAR to improve the IFDM in areas of sparse CORS.

    The third item in the proposal is to “Investigate a unified vertical reference frame, including a marine geoid optimized to be consistent with the full spectrum of observations from modern gravimetric geoids (e.g., GRAV-D, ICGEM), remotely-sensed observations (e.g., SWOT, ICESat-2), in situ ocean observations and assimilating ocean models, and the TRF.”

    The images below provide a list of the reference surfaces involved in unifying the vertical reference frames and the observing systems involved in the project. Understanding the geoid at the land-sea interchange is important to estimating accurate GNSS-derived orthometric heights along the coast as well as in the oceans. My August 2021 newsletter highlighted the concept of establishing an International Height Reference System (IHRS) so that all countries could provide physical heights across their boundaries and over the oceans. This project would support that international activity.

    From Yehuda Bock Ph.D. Presentation to the AAGS General Membership Meeting. (Image: AAGS website)
    From Yehuda Bock Ph.D.’s Presentation to the AAGS General Membership Meeting. (Image: AAGS website)

    From Yehuda Bock Ph.D.'s Presentation to the AAGS General Membership Meeting. (Image: AAGS website)
    From Yehuda Bock Ph.D.’s Presentation to the AAGS General Membership Meeting. (Image: AAGS website)

    This newsletter and my previous GPS World newsletter highlighted two of the grantees, \SIO and OSU, which included developing models to address what NGS denotes as the IFDM.

    The SIO program includes creating a formal geodesy program at SIO that will help to address the geodesy crisis. In addition to the graduate level courses, they are proposing an undergraduate course that will provide students with the skills in geospatial systems that will provide opportunities for eventual employment in the public and private sectors. My next newsletter will address another NGS geospatial modeling grant awardee – Oregon State University’s proposal.

  • Federal agencies addressing the geodesy crisis

    Federal agencies addressing the geodesy crisis

    In my last column, I highlighted the announcement made by the National Geodetic Survey (NGS) of the recipients of the NOAA FY 23 Geospatial Modeling Competition Awards. As shown in the image below, NGS awarded approximately $4 million in grant funding to four institutions for projects that will research emerging problems in the field of geodesy, develop tools and models to advance the modernization of the National Spatial Reference System (NSRS), and help address a nationwide deficiency of geodesists.

    Image: NGS
    Image: NGS

    I had the opportunity to speak with Juliana Blackwell, director of the NGS, about the geospatial awards. I asked her how the grants will help NGS in its development of products and services as well as the implementation of the modernized NSRS.

    “The geospatial modeling grant is an opportunity to expand our abilities within NGS to address research challenges, diversify the tools we provide, and multiply our future workforce,” Blackwell said. “I’m excited about the competitive and collaborative nature of the grant and the chance for NGS to work with a variety of academic institutions.”

    NGS awarded the grant funding to four institutions including Oregon State University, Scripps Institute of Oceanography, Michigan State University, and the Ohio State University. Looking at the summary of the awards, there appears to be some overlapping interest between grantees that could lead to a diverse set of solutions to a problem or task. I will report on specific tasks and outcomes as more details become available.

    I was pleased to see that grant proposals included developing new geodetic tools and operating procedures for working with the new, modernized NSRS. Hopefully, these universities will engage the geospatial user community when developing new tools so the tools will be useful during the implementation of the new NSRS.

    Summary of the Geospatial Awards (Image: NGS)
    Summary of the Geospatial Awards (Image: NGS)

    Besides providing funds for the geospatial grants, NGS is collaborating with other federal agencies to address the geodesy crisis. This collaboration, denoted as the “Geodesy Community of Practice (COP),” includes four agencies — NGS, National Geospatial-Intelligence Agency (NGA), National Aeronautics and Space Administration (NASA), and United States Geological Survey (USGS). The co-chairs of the group discussed the group’s actions and goals at the Hydrographic Services Review Panel (HSRP) fall committee meeting held in Silver Spring, Maryland, on Sept. 27-29.

    Geodesy Community of Practice. (Image: NOAA's Hydrographic Services Review Panel)
    Geodesy Community of Practice. (Image: NOAA’s Hydrographic Services Review Panel)

    The HSRP involves four NOAA offices: three National Ocean Service (NOS) program offices -NGS, the Center for Operational Oceanographic Products and Services (CO-OPS), the Office of Coast Survey (CS), and the University of New Hampshire’s Joint Hydrographic Center and Center for Coastal and Ocean Mapping. More information and the presentations from the HSRP meeting can be obtained here. The purpose of the committee is to review and provide NOAA with independent advice on their products and services.

    (Image: NOAA's Hydrographic Services Review Panel)
    (Image: NOAA’s Hydrographic Services Review Panel)

    I attended the three-day HRSP meeting as a virtual participant. As previously noted, NGS is one of the NOS offices that’s part of the HSRP. As the Director of NGS, Blackwell participated in the 2023 fall HSRP meeting. A majority of the meeting discussed the geodesy crisis. In my opinion, this is due to Blackwell’s efforts to highlight the importance of geodesy to NOAA products and services.   

    The presentation by the co-chairs of the Geodesy Community of Practice highlighted a few articles that have brought the geodesy crisis to the attention of the geospatial user community. Anyone keeping up with my columns knows that I have been highlighting the geodesy crisis and programs that advance the science of geodesy (July 2020, November 2022, December 2022, and April 2023). The geodesy crisis white paper is posted on the American Association for Geodetic Surveying (AAGS) website. 

    (Image: NOAA's Hydrographic Services Review Panel)
    Image: NOAA’s Hydrographic Services Review Panel)

    The Geodesy COP established working groups to address topics that are important to all geospatial users. All the agencies are supporting the working groups which should help create more effective and efficient solutions to technical geodetic issues.

    Image: NOAA's Hydrographic Services Review Panel
    Image: NOAA’s Hydrographic Services Review Panel

    A goal of the Geodetic Community of Practice is to train future geodesists. The advancements in satellites and computers have enabled geodesy to expand into many different disciplines.  Geodetic science and technology now underpin many sciences, large areas of engineering (such as driverless vehicles and UAVs), navigation, precision agriculture, smart cities, and location-based services. Major U.S. companies, such as Google and FedEx, as well as the automobile industry, precision farming companies and mining companies also need more accurate geodetic models, tools, and algorithms. Therefore, these companies also need trained geodesists to perform important research on topics that address their specific geodetic requirements. I highlighted this in my July 20, 2020, GPS World First Fix article. To address the geodesy tradecraft, the COP includes providing professional government assignments. That said, many industries that rely on accurate and consistent geodetic information should also provide professional geodetic assignments.   

    Training future geodesists. (Image: NOAA's Hydrographic Services Review Panel)
    Training future geodesists. (Image: NOAA’s Hydrographic Services Review Panel)

    I asked Blackwell how she thought the U.S. government’s Geodesy Community of Practice will help NGS and the geodesy crisis.

    “The Geodesy Community of Practice is in the beginning phase right now with the collaboration among federal agencies with geodetic missions, NOAA/NGS, NGA, NASA, and USGS,” Blackwell said. “There is already a benefit in sharing research, workforce, and operational needs and leveraging our resources. I envision expanded engagement with academia, private industry, and other government agencies as the community of practice matures.”

    In my opinion, the Geodesy Community of Practice’s integrated working groups consisting of individuals with different backgrounds and skills addressing geospatial problems will help to advance the field of geodesy. I believe that integrated and collaborative organizations create the best geospatial solutions; the Geodesy COP is an embodiment of this concept.

    Of course, as I have stated in many of my columns, I like to remind everyone that “geodesy is the foundation for all geospatial products and services.”

  • Surveying on a busy runway

    Surveying on a busy runway

    Image: NV5 Geospatial
    Image: NV5 Geospatial

    NV5 Geospatial, a large geospatial data company, provides services for airport projects across the United States and U.S. territories — mainly supporting airport planning and engineering firms that must meet FAA survey and mapping requirements for data collection at airports. “We generally are a sub-consultant to them, helping them achieve those survey standards for collecting the data and submitting it to the FAA,” said David Grigg, the company’s Aviation Program Director. Typically, this is around planning projects such as airport layout plans and master plans, but also engineering projects such as runway extensions and runway reconstructions.

    As an example, Grigg cited the extension of a runway, which requires new flight procedures to be established. “Two survey missions are required for runway extensions. The primary mission is to establish control for the aerial imagery. Using the imagery, control and design data, we check for obstacles photogrammetrically. That data is sent to the FAA and procedures are developed. After construction is complete, we go back to the airport to survey the changed runway and navigational aids (NAVAIDS) to verify that what was designed was ultimately built.”

    Another way in which NV5 Geospatial supports airport clients is by conducting obstruction studies around them for vegetation management. “That’s generally where we pull in the lidar surveys,” said Grigg. The FAA’s standards for relative and absolute positioning accuracy for trees are “rather generous” by surveying standards, he said. “We’re talking two to three feet vertically and twenty feet horizontally. It’s not like a typical mapping job where you’re guaranteeing it to one foot or better horizontally and half foot or better vertically.”

    The FAA, he points out, has published guidance on how lidar may be used. “We mostly use aerial photogrammetry to support projects in the FAA’s airports GIS program. When we collect lidar at an airport, we do it to generate contours and to identify individual tree canopies. Our lidar-derived data is most often developed to benefit airports for tree mitigation not for FAA airports GIS survey projects.”

    Image: NV5 Geospatial
    Image: NV5 Geospatial

    On the other hand, the FAA has strict requirements regarding metadata to document when, where, and how each control point is collected. “At the time of the survey, photographs are taken of the GPS units from different angles and cardinal directions,” Grigg said. “This is visual documentation for NGS that the surveyed point is at the location described. ”

    Another challenge for surveyors working at airports is that they are required to pull back for incoming aircraft. “Obviously, you will have some logistical issues at busy airports,” said Grigg. Surveyors are required to have special lights and markings on any vehicles that enter the airport property to ensure ground and air visibility. Aircraft movement also impacts surveyors as they must move away from the runway safety area (RSA) for take-offs and landings. Busier airports are surveyed at night, when air traffic is reduced or runways are closed.

    Image: NV5 Geospatial
    Image: NV5 Geospatial

    A typical project for a small airport takes about nine months, while for bigger airports — such as Chicago O’Hare, Dallas-Fort Worth, or Hartsfield-Jackson Atlanta — they can take up to twice as long. “The large hubs update their master plan on a more reoccurring basis, such as every three to five years,” said Doug Fuller, NV5 Geospatial’s Airport Solutions Specialist. “As the airports get smaller, you start stretching out that timeframe.”

    Airport survey requirements

    [The following was written by NV5 Geospatial and only lightly edited by GPS World.]

    Airports have surveys conducted for many different reasons. However, all survey types require the collection, classification and reporting of accurate data about the project. The methodology selected to gather the information is up to the professional surveyor’s judgment. Some features require observation through ground field methods, while others lend themselves to collection via remote sensing technologies.

    All surveys start with a search for existing airport control, which are called Primary Airport Control Points (PACS) and Secondary Airport Control Points (SACS). These are points on the airport that have been adjusted by the National Geodetic Survey (NGS). This ensures that the survey is done on the National Spatial Reference System (NSRS).

    A typical survey includes surveying the runway, the end points, any displaced thresholds, and a profile along the centerline of the runway. If the centerline marker is not in the correct location or if it is not there at all, the surveyor will make the necessary measurements to establish the proper location and set a new marker. Next the surveyor must locate all NAVAIDS and survey them at the proper location as described in FAA Advisory Circular 150/5300-18B.

    After the NAVAIDS are located, the photo control survey will be done. This still requires the PACS and SACS to be the points of origin of the survey. The base requirement as described in FAA Advisory Circular 150/5300-16C is to survey ten photo control points and five check points. The check points are sent to NGS’s Online Positioning User Service (OPUS). This is used to check that the survey was done on the NSRS and that the compilation meets FAA standards.

    The standards the surveyor must meet vary depending on the equipment type or photo control point. Examples of the accuracy requirements for the NAVAIDS are as follows:

    Point Horizontal Vertical
    Distance measuring equipment +/- 1 ft +/- 1 ft
    Glideslope +/- 1 ft +/- 0.25 ft
    Inner marker +/- 10 ft +/- 20 ft
    Localizer +/- 1 ft +/- 0.25 ft
    Runway end point +/- 1 f ft +/- 0.25 ft
    Runway profile points +/- 1 f ft +/- 0.25 ft
    Photo control +/- 1 ft +/- 1 ft

     

     

    PACS and SACS

    		 X Y Z Ellip.
    Inverse from PACS to SACS

    surveyed relative to published

    		 0.09 ft 0.09 ft 0.15 ft 0.13 ft

    When surveying on airport property, the largest challenge is always accessing the runway safety area to locate the runway ends and profiles. At small airports Surveyors must work when the runway is not busy; at airports with FAA control towers when the runway is closed. Frequently this is done overnight. Other challenges include access to the FAA NAVAIDS. Some of them must be turned off to be surveyed and others require survey points on which it is not possible to set an instrument. When we are not able to occupy a point, we collect it by surveying multiple equidistant locations around the NAVAID and averaging them.

    Image: NV5 Geospatial
    Image: NV5 Geospatial

    NV5 Geospatial surveyors use a combination of real-time (R/T) and post-processing techniques. We also use OPUS with the PACS and SACS and the five check points. Once the PACS and SACS have been determined to be stable, the proper coordinates are applied to them and the R/T points are adjusted using Trimble Business Center (TBC). NV5 Geospatial uses Trimble TRM-R8s and we recently added TRM-R12i receivers to our equipment. We use ground control points to orient the photography and to calibrate the lidar.