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September 18, 2018

Learn About USGS Hazards Science and More About National Preparedness Month: The very nature of natural hazards means that they have the potential to impact a majority of Americans every year.  USGS science provides part of the foundation for emergency preparedness whenever and wherever disaster strikes.

2018 has been an interesting year when it comes to natural hazards.  The biggest story to capture the nation's attention so far has been the most recent eruption of the Kilauea volcano on the Island of Hawaii.  With its dramatic explosions at the summit and lava fountains at the fissures, lava flows that were incredible to watch, toxic gas (otherwise known as "vog") that was detected as far as away as Guam, and dramatic plumes reaching thousands of feet in the air, Kilauea served as a reminder that ours is a living and dynamic planet that can turn treacherous in an instant.

However, Kilauea provided USGS scientists a unique opportunity to study all the aspects of this type of eruption, and we continue to use this information to keep the communities in the vicinity of the volcano aware of the danger and the best ways to ensure they take proper action to protect lives and property.  It's the same with every hazard event: As devastating as they can be, we always learn something that helps us make communities across the country more resilient.

Meanwhile, the hurricane season has also been intense and widespread: simultaneous hurricanes threatened Puerto Rico, the Atlantic seaboard, Hawaii and Guam, and moderate to major flooding has occurred in nearly every region of nation.  For instance, in August, Hurricane Lane brought record flooding to Hawaii, while communities in Texas, Florida, and Puerto Rico are still working to recover from the damaging 2017 landfalls and flooding from Hurricanes Harvey, Irma, and Maria.  In September of 2018, Hurricane Florence brought devastating flooding to large parts of the of the southeastern United States, from South Carolina to Virginia.

The more we know about hazards, the more we can guard ourselves against their destructive impacts.  The USGS is leading the way in providing information to support readiness and preparation for natural hazards.  Our scientists, emergency managers, and administrators work with federal, state, and local agencies to understand hazards, communicate their potential risks and impacts, and inform ways to mitigate large-scale loss of life and property.


USGS:  Start with Science

The USGS works with many partners to monitor, assess, and conduct research on a wide range of natural hazards. USGS science provides policymakers, emergency managers, and the public the understanding needed to enhance family and community preparedness, response, and resilience.

By understanding how the Earth behaves and identifying potential hazard scenarios, federal, state, and local agencies can perform meaningful risk analyses. For example, USGS science can be combined with information such as population distribution and construction practices to inform insurance rates; local building and land-use codes to mitigate impacts to critical facilities; inform emergency preparedness plans to ensure appropriate steps are taken before, during, and after an event; large infrastructure investments – such as dams and reservoirs – and improvements to private property standards and materials, which all help to make homes and community infrastructures more resilient to natural hazards.

Developed by the USGS, ShakeMaps facilitate communication of earthquake information beyond just magnitude and location. By rapidly mapping out earthquake ground motions, ShakeMaps portray the distribution and severity of shaking. This information is critical for gauging the extent of areas affected, determining which areas are potentially hardest hit, and allowing for rapid estimation of losses. Key to ShakeMap's success, computer programs were developed that take advantage of high-quality recorded ground motions and Internet-based reports from those that experienced an earthquake.(Public domain.)


Earthquake hazards are a national problem, with nearly half of Americans living in areas prone to potentially damaging earthquakes. The USGS has created and provides information and tools to support earthquake loss reduction for the country. These include hazard assessments, earthquake scenarios like the annual ShakeOut events and the recently released HayWired scenario, comprehensive real-time earthquake monitoring, and public preparedness handbooks.

Now, imagine if doctors could be warned to stop delicate procedures before the damaging seismic waves of an earthquake arrive; if emergency responders were provided a few moments of advance notice to act; if trains could be slowed or stopped; if airplane landings could be redirected; and people could have time to "drop, cover, and hold on." The USGS and its partners are making that a reality by building the ShakeAlert Earthquake Early Warning System for the West Coast of the United States. USGS is already issuing ShakeAlerts to pilot users. System upgrades and testing are paving the way for public alerting and rapid mass-alerting technologies are still in development by ShakeAlert partners. ShakeAlert is an innovative technology that will improve over time. The ShakeAlert System can provide vital seconds to tens of seconds of warning before the arrival of strong shaking, lending valuable time for response actions to be taken and for people to get to safety.

Earthquake Road Damage
Photographs showing examples of types of damage to lifelines and infrastructure expected to occur along the Hayward Fault in the San Francisco Bay region, California, in an earthquake like the magnitude-7 mainshock modeled in the HayWired Scenario.(Public domain.)


The United States is home to 169 active volcanoes across numerous Western states and territories. Volcanoes can show signs of unrest hours, days, and months before they erupt. The USGS operates five Volcano Observatories to detect and interpret these precursors as part of the USGS National Volcano Early Warning System. By analyzing data from its monitoring networks, the USGS issues public warnings and alerts about conditions at U.S. volcanoes, including models for ashfall forecasts and aviation notices. The USGS works with emergency-management authorities well in advance of volcanic crises to help potentially impacted communities prepare.

Volcanic activity has been very active this year, from the recent eruption of Kilauea volcano on the Island of Hawaii, unrest at Veniaminof on the Alaska Peninsula and at Cleveland in the Aleutian Islands of Alaska, to the continuous monitoring of the Yellowstone “Supervolcano” and its active hydrothermal areas that have produced steam explosions in August 2018.

During the March 2011 Kamoamoa fissure eruption on Kīlauea Volcano's East Rift Zone, spatter from this line of lava fountains just west of Pu‘u ‘Ō‘ō reached heights of 40 m (130 ft). Events of the short-lived, but spectacular, fissure eruption are summarized in the March 7, 2013, Volcano Watch article, which is available in the USGS Hawaiian Volcano Observatory's Volcano Watch archive ( USGS photo by T. Orr.(Public domain.)

Hurricanes and Tsunamis

How vulnerable is your community to hurricanes, not just to wind but also to coastal erosion due to storm surge and wavs, as well as inland flooding from extreme rainfall? USGS collects storm tide and high-water mark data for major hurricanes or tropical storms affecting the United States.  The data is accessible to the public in the USGS Flood Event View.  In addition, the USGS assesses the likelihood of beach erosion, overwash, or inundation. The USGS provides real-time impacts of approaching storms via the Coastal Change Hazards Portal. This online tool allows anyone to interact with regularly updated forecasts of hurricane-induced coastal change, as well as “see” past, present and future hazards along the coastline from local to national-level scales.

The USGS studies recent and historic tsunamis to better understand impacts, processes, and causes, with a focus on investigating earthquakes as triggers.  USGS also studies landslide and volcanic eruption-triggered tsunamis to understand all potential causes and to identify tsunamis hazard zones.  Scientists have evaluated the number of people or businesses exposed to tsunami hazards, as well as demographics and evacuation time for each of these communities. This provides officials with the ability to develop outreach, preparedness, and evacuation plans that are tailored to local conditions and needs.

Animation shows an cartoon of a coastal area, the ocean surface, and the seafloor, then waves develop and grow in size.
Preliminary simulation of the tsunami from the February 27, 2010 M=8.8 subduction zone earthquake offshore Chile. Viewpoint looks to the east from the Juan Fernández Islands toward Chile (in the distance). The first 78 minutes of propagation is shown.(Public domain.)

Floods and Drought

The USGS operates a nationwide streamgage network to monitor water level and flow in rivers and streams and compiles flood-frequency information needed to design dams, bridges, and other infrastructure, as well as to delineate floodplains. The USGS also provides essential data 24/7 for the National Weather Service flood forecasts, watches and warnings, and the time timing of releases of flood-control reservoirs across the nation. USGS science contributes to the U.S. Drought Monitor as well as the Drought Outlook led by NOAA’s NWS. On a global scale, the Famine Early Warning Systems Network identifies populations with the most food insecurity. This network is an activity of the U.S. Agency for International Development, with the USGS serving as an implementing partner.

Getting ready to measure flood waters
Hydrogropher Patrick Bowen floating equipment to the Road overflow measurement site for the Passaic River at Little Falls, New Jersey gage after peak on August 19, 2011.(Credit: Andrew Watson , USGS. Public domain.)

Landslides and Sinkholes

Landslides occur in all 50 states, and every year cause loss of life and billions of dollars in damage to public and private property. USGS science is helping assess where, when, and how often landslides occur, and how fast and far they might move. For example, USGS scientists produce maps showing where landslides might occur, and they identify what sort of rainfall conditions cause them. In southern California, the USGS partners with NOAA’s NWS to provide important advance warnings for debris-flows generated in areas burned by wildfire.

About 20 percent of the nation is at risk from sinkholes. These areas are underlain by karst, which is characterized by terrain where the underlying rock is easily dissolved by groundwater (check out more information on sinkholes at the USGS Water Science School). The USGS produces geologic and subsurface maps that help managers and others to better understand karst regions and identify local areas that may be susceptible.


Photographs looking at a coastal cliff with a road covered by a landslide, then debris is cleared and road is repaired.
Time-lapse view of California Highway 1 reconstruction after 2017 landslideUSGS scientists produced an animated GIF in coordination with the California Department of Transportation (Caltrans) re-opening of State Highway 1 through Big Sur on July 18, 2018. In 2017, the massive Mud Creek landslide buried a quarter-mile of the famous coastal route with rocks and dirt more than 65 feet deep. As part of a new research project to monitor erosion along the landslide-prone cliffs of Big Sur, USGS scientists collected aerial photos before and after the slide, and during the construction project. By analyzing overlapping photos, they made precise maps of the slopes and calculated volumes of material lost or gained over time. Our researchers shared data and images with Caltrans to help ensure the safety of workers and the success of the road reconstruction.(Credit: Andy Ritchie, USGS Pacific Coastal and Marine Science Center. Public domain.)


The USGS provides tools and information before, during, and after fire disasters to identify wildfire risks and reduce subsequent hazards, including delivery to fire managers of up-to-the minute maps and satellite imagery about current wildfire extent and behavior.

Huge blaze engulfing trees
Huge wildfire(Public domain.)

Geomagnetic Storms

Geomagnetic storms are caused by a dynamic interaction between the solar wind and the Earth’s magnetic field. The resulting rapid magnetic field fluctuations can interfere with radio communications, GPS systems, satellites and directional drilling for oil and gas. Large magnetic storms can even interfere with the operations of electric power grids, causing blackouts. For these reasons, these storms are considered hazardous for both the economy and national security.

The USGS operates a network of specially designed observatories that provide real-time data on magnetic storm conditions. These data are critical for tracking the intensity of geomagnetic storms and are used by the NOAA Space Weather Prediction Center for issuing storm warnings, and likewise by the U.S. Air Force for their operations. Through the National Space Weather Program, USGS scientists are working with other federal government agencies and private industry to assess and mitigate hazardous effects of storms to the nation’s electric power grid.

dark space with golden solar flare
Screenshot of the "Introduction to Geomagnetism" video.(Public domain.)

America’s PrepareAthon!  September 2018

Get prepared and join millions of people participating in America’s PrepareAthon! This is a campaign encouraging people across the nation to practice preparedness actions before a disaster or emergency strikes. Activities include drills, group discussions, exercises, and more.


The Great ShakeOut on October 18

Millions of people across the nation will be participating in the next ShakeOut earthquake preparedness drill, to be held on Oct. 18, 2018. At 10:18 a.m. local time, participants will “drop, cover and hold on.” Mark your calendar and sign up to join.


Resources for Further Inquiry and Study – Knowing how hazard risks can impact your area helps keep you and your family safe.  Take a few minutes to click on the links below for more information and sign up for applicable alerts to keep you informed at a moment’s notice.


Explore Your Hazards

  1. See past, current and forecasted hazards along the coasts.
  2. Get details on the latest geomagnetic disturbance event caused by solar activity.
  3. Gather info on current flooding and past incidents at the USGS flood website.
  4. Browse through statistics on water use in the United States.
  5. See the Fire Danger Forecast, which is a dynamic map updated daily (at the top right, click “view legend for selected layer[s]” to see what the colors mean).
  6. Current and past wildlife die-off information is available online—through an interactive map—to help inform disease prevention and mitigation strategies.
  7. An estimate of how long it would take for someone to travel by foot out of a tsunami-hazard zone can be calculated through the USGS Pedestrian Evacuation Analyst.
  8. See the latest earthquakes worldwide.
  9. If you live near a recent wildfire, see maps showing the potential for debris-flow activity.


Sign Up for Alerts

  1. Sign up for free notification emails about volcanic activity happening at U.S. volcanoes.
  2. See how high or low river levels are through USGS WaterWatch. Receive texts or emails when water levels in rivers and streams exceed certain thresholds through USGS WaterAlert. Or you can request data on-demand through USGS WaterNow.
  3. Sign up to receive earthquake notices through the USGS Earthquake Notification System.

Last September, we launched our USGS Natural Hazards Science Facebook page.  Along with the regular USGS Facebook page, the Natural Hazards page is a great way to keep up-to-date with natural hazards, related science, and how we are working to keep our nation aware and prepared.

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