Using data from GPS receivers and seismographs, three seismologists may have found a way to identify tsunami earthquakes in time to warn people
A few times a century, a medium-sized earthquake causes a large and devastating tsunami. The most recent occurrence was in 2010, when a magnitude 7.8 earthquake off the Mentawai Islands in Indonesia set off a tsunami that was more than 50 feet high in some places, killing 509 people and displacing 15,000.
While rare, these tsunami earthquakes are particularly dangerous because they can hit coastal communities within five to 15 minutes, before officials can issue a warning. Now, however, using data from GPS receivers and seismographs near the 2010 Mentawai event, three seismologists — Valerie Sahakian and Diego Melgar at the University of Oregon and Muzli Muzli at the Earth Observatory of Singapore — may have found a way to identify tsunami earthquakes in time to warn people.
Very large earthquakes under an ocean break both the deeper part of a subduction zone, where one tectonic plate is sinking beneath another, as well as its shallow part, in a rapid motion that creates a tsunami. Tsunami earthquakes, on the other hand, happen almost entirely in the soft, weak section of a fault, moving slower and creating much more movement on or near the sea floor compared to earthquakes of the same size that happen in rigid rock. This creates much larger tsunamis than expected. A tsunami earthquake might have the same magnitude as an earthquake that occurs in rigid rock but produces much less of what seismologists call high-frequency energy.
Currently, officials issue tsunami warnings within tens of minutes of detecting an earthquake above a certain magnitude within a certain distance of a coastal area. This method, however, fails in the case of tsunami earthquakes, which produce tsunamis that are disproportionate to their magnitude.
Indian Ocean (Jan. 2, 2005): A village near the coast of Sumatra lays in ruin after a tsunami struck South East Asia. (Photo: U.S. Navy/Photographer’s Mate 2nd Class Philip A. McDaniel)
Traditionally, scientists have detected tsunami earthquakes by comparing their seismic magnitude with the amount of high-frequency energy they radiate, both recorded by distant stations. Tsunami earthquakes have a very low ratio of energy to magnitude; their energy, instead of strong shaking, produces a large slow movement of the seafloor.
In the past, scientists had to measure this ratio using seismic waves that had traveled from the earthquake’s epicenter to seismographs hundreds or thousands of miles away. This did not give them enough time to identify tsunami earthquakes and warn people before the tsunami’s wave hit the coast.
The recent analysis, however, enabled scientists to figure out a faster way to identify these rare tsunami earthquakes by using two proxies:
data from seismic stations onshore near the epicenters of 16 earthquakes that measured directly how much the ground shook in each case, to determine the amount of high frequency energy in each earthquake, and
data from GPS stations close to the earthquakes, to measure the magnitude of each one on the basis of how much it moved the ground.
The GPS stations used in this study were from the Badan Informasi Geospasial (BIG) network from Indonesia. The data were acquired in real-time but processed with final orbits and clocks using precise point positioning (PPP). The scientists averaged the 3-component displacement, using centimeter-level solutions, and saw 3-10 centimeter vertical displacement.
This methodology, using data available during and immediately after an earthquake, enables scientists to compare the amount of energy in each earthquake with its magnitude, without waiting for their seismic waves to travel to distant measuring stations. Seismologists will be able to use this approach to identify tsunami earthquakes immediately and warn nearby coastal communities before a tsunami wave reaches them.
Citation. Sahakian, V. J., Melgar, D., & Muzli, M. (2019). “Weak near-field behavior of a tsunami earthquake: Toward real-time identification for local warning.” Geophysical Research Letters, 46(16), 9519–9528.
Previous research suggests that not until halfway through a rupture (90 seconds for a magnitude-9 quake) can magnitude be predicted. Geodetic GNSS data could bring this down to as little as 10 seconds — greatly extending and enhancing earthquake early warning systems.
How soon can we predict the magnitude of an earthquake?
Seismologists Diego Melgar of the University of Oregon and Gavin Hayes of the U.S. Geological Survey (USGS) in Golden, Colorado, tackled this question by chance while Melgar was writing code to simulate earthquakes to check the accuracy of Earthquake Early Warning systems in the Pacific Northwest.
He reached out to Hayes, who curates a database for the USGS that contains “source time functions,” which show how the seismic energy release changes through time as the earthquake ruptures.
As a rupture grows, the speed of growth changes, and source time function captures that change. Melgar and Hayes focused on the acceleration of the energy release in large (M>7) and great (M≥9) earthquakes, and found that acceleration wobbled between 2 and 5 seconds after the quakes began.
In February 2016, the USGS rolled out the second-generation ShakeAlert Earthquake Early Warning test system in California. The diagram shows how the system would operate. (Image: USGS)
However, with the approximately 250 M≥7 earthquakes in their database, they found that between 10 and 15 seconds after rupture began, these larger earthquakes started to behave similarly, and that behavior scales with their final magnitude, Hayes said. “In other words, the acceleration at 10 to 15 seconds is diagnostic of their final magnitude.”
Earthquake ruptures sputter along for about 10 seconds, after which the big ones accelerate, according to Melgar and Hayes. Three different source time function databases showed the same consistency.
Vertical movement near the source of large earthquakes can be between 3 and 5 meters, according to data from GNSS geodetic receivers. Analysis of near-source GNSS data from 12 M≥7 earthquakes showed that for the first 10 seconds after the first indication of an earthquake was recorded, the earthquakes made almost immeasurable movements. But between 10 and 15 seconds, the amount of vertical displacement began to rapidly diverge for the different magnitude groupings. By 20 to 25 seconds, the vertical movement was distinct.
Previous research indicated roughly half the source duration must pass before an accurate prediction could be made. Cutting the prediction time down to 15 seconds would be invaluable to earthquake early warning systems and tsunami prediction algorithms, where every second counts.
GNSS sensors are installed onshore across the globe, but the majority of megathrust earthquakes occur underwater. To integrate Melgar and Hayes’ findings effectively into earthquake early warning systems would require sensors installed along the seafloor, they noted. “You [would also] need to have fiber-optic cables from shore to the bottom of the ocean, winding around with sensors, and then eventually coming back on shore, and that’s not cheap,” Melgar said.
An additional 10 to 30 seconds of warning to a city or nuclear reactor of an imminent quake would have enormous benefits. But if the hypothesis is wrong, using it now would lead to a greater rate of false alarms and missed quakes, eroding the value of these warnings to society. Melgar and Hayes acknowledged their finding needs to be rigorously tested.
Summarized from Temblor’s website. The Temblor Android app and website provide earthquake, landslide, tsunami and flood information.
Citation
Tripathy-Lang A. (2019), “Can the size of a large earthquake be foretold just 10 seconds after it starts?”. Temblor, http://doi.org/10.32858/temblor.029
No, this is not a drill or a major motion picture event.
During my lifetime, many natural disasters that have taken place around the globe. These unfortunate events have created mass destruction and caused many deaths by a variety of environmental elements, ranging from earthquakes and volcanic eruptions to hurricanes and snowstorms.
Disasters in the United States. (Image: FEMA)
Once Mother Nature decides to unleash her wrath, rarely anything stands in her way. Some types of disasters create situations worse than others, but all have a reputation of leaving a trail of death and destruction.
Search and rescue is the first and foremost priority when it comes to these disasters, with cleanup and rebuilding to soon follow.
The role of the land surveyor, however, doesn’t usually enter the discussion when it comes to these situations. It has always been considered an occupation that fills an important role in development, construction and parcel ownership, but rarely is discussed in the same terms as a fireman, policeman or doctor.
We will take a closer examination at how the surveyor uses skills developed through education, technical training and practical application of geographical data to quietly assist those in need through these difficult bouts with Mother Nature.
First, however, we will discuss various types of the deadliest natural disasters, the amount of destruction that has been caused and types of problems (besides deaths) that were left because of these tragedies.
Disasters throughout history
When describing natural disasters, the obvious ones come to mind: earthquake, hurricane/typhoon/cyclone, tornado, wildfire, flooding/monsoon, drought/famine, volcanic eruption, tsunami, sandstorm, avalanche, and snowstorm.
All of these have wreaked havoc on mankind for centuries, with more physical destruction taking place in the past few centuries.
Some of the factors leading to an increase in this devastation are gains overall population and amount of buildings and improvements in populated areas. Let’s look at how each disaster impacts the areas in which it occurs:
Flooding/Monsoon
Historically the deadliest type of natural disaster, rainfall through storms and monsoons cause flood events that have caused millions of deaths in several instances around the world. Most of the deaths caused by flooding situations are due to drowning in floodwaters that inundate areas not normally affected by normal amounts of rain.
The largest flood in recorded history took place in China during 1931, combining melting snow and ice with ongoing rain events to create a continuous flooding event that lasted most of the year. Death toll estimates range from 400,000 to almost 4 million, as many of the victims either died or moved to other regions with no trace.
Hurricane/Typhoon/Cyclone
This is another type of flooding disaster, but it combines large amounts of rain gathered from ocean storms with high winds to batter shoreline and inland areas. These storms can often stall in place, causing significant damage by both wind and rain.
Tornado
Most weather systems associated with creating tornadoes are believed to occur in the United States, but they happen all over the world. Many of the deadliest tornadoes have taken place in the Middle East, including Bangladesh, Russia and Pakistan. These storms can include torrential rain, but most of the damage caused by tornadoes is wind-related.
Earthquake
Shifting tectonic plates and earth-shaking tremors are a significant cause of damage and deaths throughout the world. Most of the highest death tolls have taken place in Asia, with the biggest loss of life occurring in Shaanxi, China, on Jan. 23, 1556, with more than 830,000 deaths.
Indian Ocean (Jan. 2, 2005): A village near the coast of Sumatra lays in ruin after the Tsunami that struck South East Asia. (Photo: U.S. Navy/Photographer’s Mate 2nd Class Philip A. McDaniel)
Tsunami
Often a secondary disaster generally associated with earthquakes in coastal areas, tsunamis kill thousands by inundating shorelines with huge waves and sending vast amounts of water into low-lying areas and poorly constructed seaside villages. The largest tsunami in recent memory was on Dec. 26, 2004, in the Indian Ocean off the coast of Indonesia, with the death toll reaching 280,000 people.
Volcano
The biggest cause of earthquakes is typically molten lava expanding to shift tectonic plates, but volcanoes are formed with the lava and associated gases finding an escape in the Earth’s crust.
Once a volcano has formed, an eruption can lead to significant damage from lava flow onto adjacent land and hot ash spewed into the atmosphere. Many volcanic eruptions throughout history have buried local cities and villages, making them virtually disappear.
Wildfire
Grabbing the headlines more recently has been the proliferation of wildfires. While not causing the substantial loss-of-life associated with many other natural disasters, wildfires are responsible for scorching hundreds of thousands of acres of forest and brush areas, as well as decimating neighborhoods.
Avalanche
This disaster only takes place in locations with significant snow pack and elevation changes. After large amounts of snowfall, various factors lead to movement of large areas of snow and ice down mountainous slopes. Often these events take place near cities and villages in mountainous regions and can leave the inhabitants buried and unreachable.
Other Types of Natural Disasters
While the varieties of events listed above can create large-scale destruction, there are others that, while smaller in nature, can collectively cause great damage and loss of life. Thunderstorms, snowstorms and sandstorms are wind-related and can be devastating to the areas being affected.
Other natural disasters that often don’t get the same recognition as those listed above include drought and famine. These environmental tragedies ruin thousands of lives, and it take years to recover from the damage caused by these inflictions.
Disaster hits. Now what?
June 28, 2008: A house in Parkersburg, Iowa, is being rebuilt while debris from a deadly EF5 tornado still covers the ground. (Photo: FEMA/Richard O’Reilly)
All of these disaster types have led to a great number of fatalities and total devastation of cities and roadways. To help us understand what type of assistance the surveyor can provide, we first need to identify the conditions left by each of these events.
Most of the disasters simply wipe out whatever is in its path; from tornadoes, hurricanes, and wildfires to earthquakes, avalanches and tsunamis, the regions affected are left in shambles after the occurrence.
The initial search and rescue through the rubble takes manpower and careful identification of areas where people are known to inhabit, either as residences, places of employment or public spaces. These areas require retracement of existing mapping and atlases to accurately identify those places for timely recovery.
Once the search-and-rescue efforts have ceased and cleanup/rebuilding commences, the destroyed areas will need to be remapped based upon existing parcels and ownership rights. Reconciliation of existing parcels, subdivisions and rights-of-way will be required to properly return the injured areas to a habitable state.
The one disaster that’s a big wildcard, however, is the earthquake. The devastation is like the others and generally will need rebuilding like the others, but with one large difference; putting everything back where it belongs.
When large tremors cause significant shifts in inhabited and/or complex parcels, the ability to retrace existing parcels, subdivisions and rights-of-way to place them in their original location becomes a nightmare.
How surveyors and GNSS help before and after disasters
As expert measurers and establishers of boundaries, the surveyor provides guidance for the creation of parcels and rights-of-way. Through extensive education, training and experience, the surveyor combines field reconnaissance, legal definitions of parcels and high-level mathematics to provide direction for the creation and retracement of real property.
After experiencing a devastating event like the ones described above, the surveyor becomes a key position in rebuilding the affected area.
Prior to the invention and proliferation of GNSS technology, however, the use of state plane coordinate data was a tedious and time-consuming task (see my January 2017 article at GPS World).
Establishing coordinate values across a large region and/or utility system was not practical from a time or cost viewpoint. The arrival of GNSS technology in the 1990s changed that situation with the ability to determine coordinate values in real-time and create large databases of infrastructure and utility information. Government agencies (and surveyors) now could replicate, with acceptable accuracy and precision, locations of improvements and utilities throughout their jurisdiction.
Surveyors are now being called upon to assist with search and rescue efforts when these disasters hit to help locate and turn off existing utilities (i.e. electricity, gas, water), and to provide mapping assistance for retracing where people may be in the rubble. Because lives are at stake, timely location is essential for these services and GNSS technology use by the surveyor provides a much-needed service.
Once these disaster events being a rebuilding mode, the surveyor steps in to find the existing parcel and right-of-way lines to assist the respective owners where a deed or roadway was previously located. Most times, the surveyor can retrace existing line by locating buried monuments and recreating existing deed descriptions and/or roadway locations.
Where there becomes a problem is when the devastation is large enough to destroy all existing monuments and leave no trace of any occupied land. The surveyor must expand the search area, as far as needed, to find the closest available monuments in which to begin rebuilding the parcel descriptions.
Depending on the site conditions, GNSS equipment is used to locate the positions of the nearest monuments so the surveyor can perform retracement calculations for the disturbed area.
Once the area to be re-established to calculated, the surveyor can return to the site and place markers signifying parcels and rights-of-way for the rebuilding of roads, utilities and buildings. GNSS receivers are again utilized to increase the proficiency of the field crew by allowing the installation of the markers over a large area in a short amount of time.
How surveyors can prepare for future events
Image: DuPage County, Illinois, GIS
As previously written in my January 2017 column, GNSS technology has helped expand geographic information systems (GIS) into a database beast, containing everything from voter districts, zoning regions and floodplain maps to locations of most municipal utility maps and databases.
When these databases have included a geodetic layer of survey information overseen by the licensed land surveyor, the GIS is now more than a glorified digital Etch-A-Sketch. These entities within the database have geolocation as part of its dataset, with varying accuracy depending on the source of the data.
By having all this information available in a digital format, typically saved in a cloud-computing location, the ability to replicate these entities becomes a simple exercise. As more information becomes available, it needs to be included into the database for future mapping consideration.
All relevant data, together with a geolocation tag, becomes valuable for future retracement. This information could be used to locate possible survivors during a disaster event.
Upcoming technology to assist surveyors with disaster relief planning
Image: Esri
Many of the tools being utilized by surveyors have the capability of helping with mapping and data collection of municipal and public facilities for GIS database inclusion.
We currently use laser and lidar scanners both terrestrially and aerially to collect point-cloud data for establishing existing conditions of various sites. This point cloud, along with high-resolution photography, can be used to augment and enhance new and existing GIS databases with extensive datasets.
By having this additional information collected and available digitally, qualified experts can perform disaster simulation tests to depict various environmental events and determine what strategies will be necessary for search-and-rescue efforts.
These experts can also use this data to predict potential flood paths, conduct seismic modeling to determine building shift, and combine weather conditions with conceivable wildfire-capable areas. All these potential life-saving exercises can utilize the surveyor as a significant data-collection source.
Coming to a theater near you…
Whether one believes in climate change or just being affected by an active environmental cycle of natural disasters, the entire world is prone to have an occurrence of at least one of these events.
Since these events are not going away, remember to help your fellow man, woman or child in their time of need. It is the duty of the surveyor to provide a service that is intended to protect the public, and being there for disaster planning, prevention and recovery is part of our mission.
Think of us like the Avengers; now there’s a sequel I’d pay to see.
Researchers testing a satellite-based earthquake early warning system developed for the U.S. West Coast found that the system performed well in a “replay” of three large earthquakes that occurred in Chile between 2010 and 2015, reports the Seismological Society of America.
The results, reported in the journal Seismological Research Letters (SRL), suggest that such a system could provide early warnings of ground shaking and tsunamis for Chile’s coastal communities in the future.
The early warning module, called G-FAST, uses ground motion data measured by GNSS to estimate the magnitude and epicenter for large earthquakes — those magnitude 8 and greater. These great quakes often take place at subducting tectonic plate boundaries, where one plate thrusts beneath another plate, as is the case off the coast of Chile and the U.S. Pacific Northwest.
Using data collected by Chile’s more than 150 GNSS stations, Brendan Crowell of the University of Washington and his colleagues tested G-FAST’s performance against three large megathrust earthquakes in the country: the 2010 magnitude 8.8 Maule, the 2014 magnitude 8.2 Iquique, and the 2015 magnitude 8.3 Illapel earthquakes.
G-FAST was able to provide magnitude estimates between 40 to 60 seconds after the origin time of all three quakes, providing magnitude estimates that were within 0.3 units of the known magnitudes. The system also provided estimates of the epicenter and fault slip for each earthquake that agreed with the actual measurements, and were available 60 to 90 seconds after each earthquake’s origin time.
“We were surprised at how fast G-FAST was able to converge to the correct answers and how accurately we were able to characterize all three earthquakes,” Crowell said.
Most earthquake early warning systems measure properties of seismic waves to quickly characterize an earthquake. These systems often cannot collect enough information to determine how a large earthquake will grow and as a result may underestimate the earthquake magnitude—a problem that can be avoided with satellite-based systems such as G-FAST.
It’s difficult to test these types of early warning systems, Crowell noted, because magnitude 8+ earthquakes are relatively rare. “We decided to look at the Chilean earthquakes because they included several greater than magnitude 8 earthquakes, recorded with an excellent and consistent GNSS network. In doing so, we would be able to better categorize the strengths and weaknesses in G-FAST.”
ShakeAlert
The Chilean tests will play a part in furthering developing G-FAST for use in the U.S., where Crowell and colleagues have been working to include it in the prototype earthquake early warning system called ShakeAlert, now operating in California, Oregon and Washington. The Chilean earthquakes, Crowell said, represent about half of magnitude 8 events in the recorded catalog of earthquakes that are used to test G-FAST and other geodetic algorithms for inclusion in ShakeAlert.
Ten magnitude 8 or greater earthquakes have occurred along the Chilean coast in the past 100 years, including the 1960 magnitude 9.5 Valdivia earthquake, which is the largest earthquake recorded by instruments. “The hazard due to these large events is well recognized and understood,” in Chile, wrote Sergio Eduardo Barrientos of the Universidad de Chile, in a second paper published this week in SRL. “Return periods for magnitude 8 and above events are of the order of 80 to 130 years for any given region in Chile, but about a dozen years when the country is considered as a whole.”
After the 2010 Maule earthquake, the country began installing a network of digital broadband seismic and ground motion stations, GPS stations, and GNSS stations to provide accurate information for tsunami warnings and damage assessment. Since 2012, the Centro Sismológico Nacional at the Universidad de Chile has operated more than 100 stations, and has recently begun to operate almost 300 strong-motion accelerometers that measure ground shaking.
In a third paper published in SRL, Felipe Leyton of the Universidad de Chile and colleagues analyze data collected from 163 of these strong-motion stations to learn more about the local site conditions of underlying rock and soil in these areas. Site conditions can modify the shaking of large earthquakes and control the damage to buildings and other infrastructure caused by the shaking.
The new study “gives us a unique opportunity to improve our knowledge of the behavior of soil deposits during earthquakes, especially in urbanized areas,” write Leyton and colleagues, who say the data could be used to help improve building designs and codes.
Fugro’s laser airborne depth sounder (LADS) technology is being deployed in New Zealand to assist in relief efforts following the damaging 7.9 magnitude earthquake near Christchurch on Nov. 14.
At the request of the New Zealand Government, the Royal Australian Navy LADS flight is to conduct a rapid hydrographic survey of the seafloor in the coastal margins of the north east coast of the South Island.
“We will fly over the area and collect hydrographic survey data, which will reveal what has happened below the waterline, and identify any shifts in the ocean floor which mariners need to be aware of,” explained Flight Lieutenant Commander Susanna Hung, who is serving as the mission’s commanding officer.
The navy’s airborne lidar bathymetry (ALB) system has been developed by Fugro for safe, high speed and cost effective surveys of shallow coastal areas. Under a long-term contract to the RAN, Fugro provides the LADS technology, a de Havilland Dash 8-202 aircraft and support services.
Fugro’s LADS technology is being deployed following the Nov. 14 New Zealand earthquake.
The airborne survey equipment is operated by navy personnel from the main cabin of the aircraft to rapidly collect high resolution data of the seafloor. Fugro’s system incorporates sophisticated sensors that utilize a high-powered laser, innovative scanner and receiver optics technology.
The survey tool complements traditional hydrographic survey methods (such as hull-mounted multibeam echo sounders) to support nautical charting and coastal zone management applications in the nearshore/shallow water environment. The speed of deployment and safe operating capability make it an ideal solution to confirm the safety of navigation and locate new hazards such as is now required in the earthquake affected area.
“The New Zealand deployment by RAN LADS is an excellent example of how our innovative technology can assist in the safety of navigation and management of the marine environment,” said Paul Seaton, Fugro’s regional business development manager.
Operators of UK transport networks will be the first to benefit from Live Land, a satellite-based land monitoring system developed through the European Space Agency (ESA).
Transport operators across the UK face significant challenges in monitoring and detecting landslides and subsidence across their networks. Geological hazards in the vicinity of roads and railways can disrupt business and communities.
The Live Land demonstration project will help to assess and monitor high-risk areas by providing more information on geological hazards along rail and road networks using integrated data from GNSS and Earth observation satellites.
CGG GeoConsulting‘s NPA Satellite Mapping group has been awarded a contract to lead the Live Land project, sponsored by the ESA within its Integrated Applications Program (IAP). Over the next two years, the Live Land consortium will develop a number of products for two prominent Scottish transport operators, Network Rail (Scotland) and Transport Scotland.
Once successfully demonstrated in Scotland and regions of England, Live Land is expected to expand across the UK and continental Europe as the project team engages with other transport operators who could benefit from the new information that will be available on geohazards.
The Live Land demonstration project is the follow-on of a previous ESA IAP feasibility study concluded in 2014 and draws on expertise from a team of internationally respected authorities in their respective fields:
Live Land offers transport operators increased information on geological hazards, such as landslides and subsidence. (Photo: ritish Geological Survey NERC)
How it works
Radar images from Europe’s Sentinel-1A observation satellite detect surface motion changes with millimeter precision. This is complemented with data from satnav receivers and sensors installed for in-situ monitoring in specific locations. This space-based information is combined with knowledge about the geology of the area and weather forecasts. For example, an area of steep slopes and wet soil that is expecting heavy rainfall is at a higher risk of a landslide.
Furnished with such knowledge, transport operators can assess the risks and improve their planning and response to incidents.
“Live Land integrates data collected from different sources to assess and monitor potential geological threats for transport operators,” said ESA’s Roberta Mugellesi. “Combining space-based data increases the confidence in risk assessment and predictions.”
NPA Satellite Mapping
The NPA Satellite Mappingconsultancy derives geospatial intelligence from satellite imagery. Its mapping solutions are used around the world by a client base ranging from oil and gas operators to transport asset owners to maximize operational insight and minimize risk. The company has considerable experience in geohazard research projects for ESA and European Commission, and, with its expertise in satellite InSAR (surface deformation) mapping, is optimally placed to coordinate and bring to market the unique monitoring solutions that will be developed within the Live Land project.
The services are expected to range from regional geological hazard susceptibility and activity datasets that exploit satellite InSAR measurements, to hazard forecasting models using geological and meteorological data, and the development of cost-effective, multi-sensor devices (GNSS receiver and inertial sensors) for in-situ monitoring.
“Live Land will initially play a crucial role in helping to better understand, monitor and forecast geological hazards across the UK’s road and rail networks,” said Claire Roberts, Live Land project manager and remote sensing consultant with NPA Satellite Mapping. “The developments targeted in the project are ambitious but necessary given the scale of the issues we want to address.”
CoreLogic, a residential property information, analytics and data-enabled services provider, today released an expanded version of its natural catastrophe risk management solution, which features a new comprehensive probabilistic flood model that analyzes the potential damage and financial impact at the property-level from flood events in the continental United States.
This probabilistic flood model is unique to the industry because its riverine and flash flood risk components provide better risk estimation for areas outside the 100-year flood zones–areas responsible for 20 percent of historic flood losses but which represent only 1 percent of the flood insurance policies in force.
Measuring both severity and frequency of flood events, the probabilistic flood model loss calculations offer property, contents and business interruption analysis. The model also incorporates historical flood event footprints from the last 50 years and the accompanying property damage.
Additionally, the model incorporates detailed user-provided building information to derive vulnerability assessments driven by both water depth and water velocity. These building characteristics include construction type, occupancy, floor elevation, basements and elevated building configurations. The new CoreLogic flood model provides insurers with an unprecedented tool to more accurately underwrite the risk associated with this complex peril, especially the proprietary flash flood component.
With granular 10-meter elevation data, the catastrophe risk management solution incorporates the Digital Flood Insurance Rate Maps (DFIRMs) provided by the Federal Emergency Management Association (FEMA). It uses more than 80 different occupancy classes covering topography, land-use, stream coverage and inundation. In order to more accurately measure a property’s flood risk, more than 50 data layers ranging from elevation, hydrologic and catchment information are included, as well as data for over 6 million miles of streams and 20,000 stream flow gauges.
“The release of the U.S. Inland Flood Model means insurers can now use this advanced probabilistic tool to help them determine a property’s potential for flood damage,” said Tom Larsen, CoreLogic product architect. “The model’s unique ability to provide granularity down to the property level will offer insurers a complete view of flood risk, including contents and business interruption, for all types of properties.”
The catastrophe risk management solution contains parcel-level geocoding through PxPoint from CoreLogic, which can convert physical addresses or locations into precise geographic coordinates for over 142 million parcel boundaries. A new visualization feature identifies details in the data as well as exceptions via easy-to-use charts and graphics. Other new components include updates to three risk assessment models including Italy Earthquake, the North Atlantic Hurricane Risk and U.S. Offshore Energy.
Highlights include:
The Italy Earthquake Model now incorporates an updated seismic source model based on the Seismic Hazard Harmonization in Europe (SHARE) to provide a current and more accurate view of seismic hazard in Italy. Increased maximum magnitudes, an updated magnitude-frequency distribution and a new ground motion model are part of the enhancements.
The North Atlantic Hurricane Risk Model update includes a high-resolution storm surge model and enhanced hazard risk assessment to more accurately capture the damage from storm surge as the surge attenuates inland (outside of the high velocity zones). It uses storm intensities from historical events based on the Atlantic hurricane reanalysis project by the National Oceanic and Atmospheric Administration (NOAA). Additionally, the North Atlantic Hurricane Risk Model includes a full set of default secondary structural modifiers by vintage and location for all hurricane states, which are based on the International Building Code as well as state-specific building codes to provide refined results. RQE 16 also includes a model version which was certified by the Florida Commission Hurricane for Loss Projection Methodology in June 2015.
The U.S. Offshore Energy Model features a distinctive wave model component and unique financial model which produces an improved estimate of potential damage to physical assets in U.S. territorial waters within the Gulf of Mexico. A network analysis is also built into the model to produce a better estimate of the lost production from oil wells.
“All of these enhancements will help insurers understand hazard risk in a more granular and comprehensive way, and this precision in risk modeling will help the industry overall fine-tune its underwriting, claims and reinsurance efforts,” Larsen said.
Sixty seconds may not sound like much, but if given advance warning of an earthquake, people could take cover, trains could stop, and oil rigs could be shut down before the shaking hits.
The earthquake early warning app QuakeAlert, by Early Warning Labs, aims to provide that extra time. The app, with new technology developed in partnership the United States Geological Survey (USGS), will be tested by the USGS, the California Institute of Technology and other university researchers.
QuakeAlert is designed to alert users with a countdown to when shaking will strike their exact location, and tell the user how severe the intensity is expected in their location. The app simultaneously delivers important safety instructions to the user on how to respond if indoors, outside or in a moving vehicle. QuakeAlert will be provided to users free of charge.
The QuakeAlert app uses USGS seismic sensor network data, an Esri GIS backend and the Microsoft Azure cloud to deliver earthquake early warnings. The app is currently in private beta testing with university researchers at CalTech and USGS scientists, and will be available to the public for free once the USGS receives full funding of its early warning program and approves the technology for the public.
Early Warning Labs (EWL) is an Earthquake Early Warning technology developer and integrator in Santa Monica, Calif., and an official research and development partner with the USGS. Early Warning Labs is collaborating with university partners including Caltech, Berkeley and the University of Washington, as well as Esri.
The April 25 magnitude 7.8 earthquake in Nepal created waves of energy that penetrated into Earth’s upper atmosphere in the vicinity of Nepal, disturbing the distribution of electrons in the ionosphere. These disturbances were monitored using GPS signals received by a science-quality GPS receiver in Tibet, a neighboring region to Nepal.
The data show that after the initial earthquake rupture (indicated by the vertical black line on the graphic), it took about 21 minutes for the earthquake-generated ionospheric disturbance to reach a GPS station (LHAZ) about 400 miles (640 kilometers) away from the epicenter in Lhasa, Tibet, China.
Image Credit: NASA/JPL/Ionosphere Natural Hazards Team
The disturbance measurements, known as vertical total electron content (VTEC) (depicted in blue in the upper panel), have been filtered using processing software developed by NASA’s Jet Propulsion Laboratory in Pasadena, Calif., to show wave-like disturbances (circled in red) in the distribution of electrons in the ionosphere. The waves have periods of between two and eight minutes in length. The disturbance measurements following the earthquake rupture are circled in black in the lower panel. The colors represent the relative strengths of the earthquake-induced ionospheric disturbances as captured by the GPS signals, with red being high and blue being low.
Attila Komjathy, a principal investigator of the Ionospheric and Atmospheric Remote Sensing group at JPL and adjunct professor at the University of New Brunswick, is leading this effort. Komjathy is also a GPS World annual award winner and named a Fellow of the Institute of Navigation in January.
The LHAZ GPS station is hosted at the Tibet Autonomous Regional Bureau of Surveying and Mapping Institute. The site collects both GPS and GLONASS (the Russian global navigation satellite system) data at a rate of 1 Hertz and is part of the International GPS Service (IGS).
Scientists study ionosphere-based measurements caused by natural hazards such as earthquakes, volcanic eruptions and tsunamis to better understand wave propagation in the upper atmosphere.The ionosphere is a region of Earth’s upper atmosphere located from about 37 miles (60 kilometers) to 621 miles (1,000 kilometers) above Earth’s surface.
The disturbances caused by earthquakes help scientists develop new first-principle-based wave propagation models. These models may become part of future early warning systems for tsunamis and other difficult-to-detect natural hazards.
Compare pre- and post-earthquake imagery from Airbus Defence & Space to explore damage around Nepal. This map includes several bookmarks to help users navigate around key points of interest and landmarks that were damaged or destroyed.
Users can interactively explore demographic information about the people affected by the earthquake. The map fuses demographic data with the Shakemap from USGS to provide estimates about the population in each shake zone. Click a zone on the map to see how many people live in that area.
Compare pre- and post-earthquake imagery from Airbus Defence & Space to explore damage around Nepal. This map includes several bookmarks to help users navigate around key points of interest and landmarks that were damaged or destroyed.
Users can interactively explore demographic information about the people affected by the earthquake. The map fuses demographic data with the Shakemap from USGS to provide estimates about the population in each shake zone. Click a zone on the map to see how many people live in that area.
Aeryon Labs, GlobalMedic and Monadrone are working together to deploy three unmanned aerial systems (UAS) in Nepal to help locate earthquake survivors. The drones are outfitted with thermal cameras and the Aeryon HDZoom30 camera, which has an extended zoom, to look at targets from more than 1,000 feet away.
On Saturday, April 25, a 7.8 magnitude earthquake struck Nepal — the largest quake in 81 years in the region. More than 4,000 people have died, with death tolls expected to rise as the rubble is cleared.
In response, Aeryon Labs deployed three of its sUAS (small UAS) and a qualified Aeryon pilot to the affected region. Aeryon is collaborating with partners GlobalMedic and Monadrone to provide aerial support to international disaster relief teams on the ground.
The Global Medic UAV team responded immediately to the crisis in Nepal. “sUAS provide us the unmatched capability to get onsite and into the air immediately to start determining how and where to provide support to the people,” said Rahul Singh, executive director of GlobalMedic.
Damage to, or the complete loss of, fundamental infrastructure such as airstrips and refueling facilities can make manned aircraft operations in disaster relief scenarios very challenging. Sending rescue workers into damaged structures, or rubble piles, to search for survivors also puts them in harm’s way. sUAS enable ground-based rescue teams to collect critical visual intelligence and deploy rescue resources quickly, carefully and exactly where they are most needed, the companies said.
The Aeryon HDZoom30 is a fully-integrated, ruggedized, high performance electro-optical camera payload for UAS.
The Aeryon sUAS being sent to Nepal are equipped with thermal cameras to help locate survivors by detecting body heat, as well as the companies newest imaging payload, the Aeryon HDZoom30, which can be used at extended distances to zoom in to see a target with clarity and detail. For example, operators are able to recognize a face from more than 1,000 feet (300 meters) away. The team will also undertake aerial mapping of the affected areas, building 2D and 3D maps, so that further response efforts can be planned.
“At Monadrone, we see sUAS as mission-critical tools that not only support day-to-day military, police and fire department needs, but can also play a vital role when disaster strikes,” said Robin Morris, director at Monadrone, Monaco. “The images the Aeryon sUAS will capture will enable the creation of up-to-date maps required to aid the disaster relief in Nepal.”
Aeryon sUAS were also deployed in the aftermath of the August 2014 landslide that devastated the region along the banks of the Sunkoshi River in northern Nepal. Despite the high altitude of Nepal, which is challenging for many aircraft, and the rugged terrain, Aeryon sUAS proved effective and more than up to the task.
“UAS are uniquely able to provide immediate support for disaster relief, like the earthquake in Nepal, helping rescue teams search more effectively, efficiently and safely,” Dave Kroetsch, president and CEO of Aeryon Labs, told AUVSI News. “It’s an honor to see the technology you create make such a difference. We are privileged to be able assist the aid workers who are helping the people of Nepal.”
