A "very big event" is exactly what scientists Simon Day and Steven N. Ward envision with the potential collapse of the Cumbre Vieja volcano in the Canary Island chain off the western coast of Africa. The center says it provides "cutting-edge" risk research for business, government and international agencies. Ward, a research geophysicist at the University of California at Santa Cruz, applied Day's theories about the Cumbre Vieja volcano to a computer model.
Based on evidence of a dozen major volcanic collapses in the Canary Islands over millions of years, the scientists say the western flank of Cumbre Vieja is due to give way during a future volcanic eruption. The last three eruptions were in , and In an interview Monday, Ward compared the vast layers of volcanic ash collecting on the mountain to roof shingles being piled high.
They estimate the falling chunk could be the size of a small island, perhaps 9 miles long and 9 miles wide. They say it would drop almost vertically from the Cumbre Vieja's especially steep slope and straight into waters measuring 4, feet deep.
Ward likened it to dropping a vast quarry into the ocean from several hundred feet. The energy released would be equal to all the electricity consumed in the United States over six months. Within two minutes, a massive splash or "water dome" reaches 3, high.
Within an hour, waves up to feet sweep through the islands and crash along the African mainland. In three to six hours a tsunami miles long arcs across the Atlantic, hitting Spain and England with small waves. The north end of the arc brushes Newfoundland with 32 foot waves; the south end hits South America with 65 foot waves. It likely would go several miles inland and result in trillions of dollars of damage, the paper says.
Not wanting to scare the public, the scientists add several caveats: The volcanic eruption would happen gradually, affording time to prepare; the model envisions the mountainside collapsing in one piece; and there's no telling how many eruptions it would take to bring about the collapse.
Day could not be reached Monday for comment but has said that the "short-term and medium-term" risks of a collapse are "negligible. Employees in the News. Emergency Management. Survey Manual. Significant earthquakes around the Pacific rim have generated tsunamis that struck Hawaii, Alaska, and the U. One of the largest and most devastating tsunamis that Hawaii has experienced was in from an earthquake along the Aleutian subduction zone.
Runup heights reached a maximum of 33 to 55 feet and killed people. The tsunami generated by the magnitude 9. Since the only major tsunami-generating subduction zones in the Atlantic Ocean are along the Caribbean Sea, tsunamis in the Atlantic have been relatively infrequent.
The most noteworthy tsunami resulted from the magnitude 7. The maximum tsunami runup was 6 to 23 feet, which was concentrated on the coast of Newfoundland, although it was recorded as far south as South Carolina. A couple of tsunamis reported from Caribbean earthquakes had runups of less than 3 feet. Executive SummaryNatural hazards—including earthquakes, tsunamis, volcanic eruptions, landslides, hurricanes, droughts, floods, wildfires, geomagnetic storms, and pandemics—can wreak havoc on human communities, the economy, and natural resources for years following an initial event.
Hazards can claim lives and cause billions of dollars in damage The most powerful of these natural hazards occur in subduction zones, where two plates collide and one is thrust beneath another.
The U. Scientists at the U. Geological Survey USGS have developed a new mapping tool, the Pedestrian Evacuation Analyst, for use by researchers and emergency managers to estimate how long it would take for someone to travel on foot out of a tsunami-hazard zone. The magnitude 9. The earthquake was felt throughout most of mainland Alaska, as far west as Dutch Harbor in the Aleutian Islands The tsunami scenario is a collaboration between the U.
On March 11, , the Tohoku earthquake and the resulting tsunami devastated Japan with a disaster of unfathomable proportions.
Although this pales in comparison to the loss of lives and property in Japan, the U. Government must ask whether Geological Survey and cooperating scientists have recently assessed the effects of a magnitude 7. A quake of comparable magnitude struck the southern Puget Sound region about 1, years ago, and similar earthquakes are almost certain to occur in the future.
The region is In December , when a tsunami killed more than , people in 11 countries around the Indian Ocean, the United States was reminded of its own tsunami risks. In fact, devastating tsunamis have struck North America before and are sure to strike again. Executive SummaryPuerto Rico and the Virgin Islands are located at an active plate boundary between the North American plate and the northeast corner of the Caribbean plate.
The region was subject in historical times to large magnitude earthquakes and devastating tsunamis. A major downward tilt of the sea floor north of Puerto Rico and the Virgin USGS science provides part of the foundation for emergency preparedness whenever and wherever disaster strikes. If you do not want your e-mail address released in response to a public-records request, do not send electronic mail to this entity. Instead, contact this office by phone or in writing.
Contact Webmaster about this website's content, services, or technical issues. Skip to content. Search When autocomplete results are available use up and down arrows to review and enter to select. Quick Links for Emergency Management Department. Special Needs. Alert Sign Up. Emergency Management Office. What to Do in the Event of a Tsunami Tsunamis are a series of waves following seismic events.
Review your five steps on your Pathways to Preparedness. A tsunami can travel at speeds of to mph. A major tsunami will cross an entire ocean before it slows and rises in a towering wall of water. Meteorologist Bart Hagemeyer from the National Weather Service says an earthquake in the Caribbean region is likely to project wave energy more to the north and less toward Florida.
But the direction can vary and much of the outcome depends on the amount of energy released by the earthquake. The highly unlikely tsunami that Florida might keep in mind could come from across the Atlantic, created by the collapse of a volcano in the Canary Islands off the coast of Africa, say experts.
0コメント