Share

Scientists Used GPS to Forecast 2012 Costa Rica Earthquake

By Laura Dattaro
Published: December 25, 2013

Cracks on the external walls of the Monsenor Sanabria hospital in Puntarenas, 90 km northwest of San Jose, on September 5, 2012, after a powerful 7.6-magnitude earthquake struck Costa Rica's Pacific coast. Seismologists working in the area had forecasted the possibility of such a quake. (Ezequiel Becerra/AFP/GettyImages)

On September 5, 2012, one plate of the Earth’s crust slipped below another 25 miles beneath the surface of Nicoya, Costa Rica, triggering a magnitude 7.6 earthquake. But unlike many other quakes, this one was not entirely a surprise.

Earthquakes of magnitude 7 or greater have occurred at this plate interface in 1853, 1900 and 1953. When the 1990s rolled around, scientists knew to expect another one sometime in the coming years. They began studying the region with ground-based GPS and seismic measurements, which led to accurate predictions of where an earthquake was likely to occur and that the quake would reach a maximum of magnitude 7.8.

The fault where the quake occurred is what’s known as a subduction zone, where one plate slides under another. The movement of the plates causes the Earth itself to change, allowing the team of scientists to track land movement and figure out areas of growing tension that will eventually be released in an earthquake, Andrew Newman, a Georgia Institute of Technology associate professor and one author of a new study detailing the research, told weather.com. The plates are in a state seismologists call “locked up.”

Andrew Newman performs a GPS survey in Costa Rica's Nicoya Peninsula in 2010. (Lujia Feng)

“Where that fault locked up starts to build energy for future earthquakes, but what it also tends to do is deform the land,” Newman said. “So we used the deformation of the land to map out the area that’s locked up.”

The Nicoya Peninsula is geologically rare in that a vast majority of subduction zones — more than 90 percent, Newman said — are not under land, but under water, such as the Cascadia zone off the Pacific Northwest of the United States or the Tohoku region of Japan, where a massive magnitude 9 earthquake triggered a devastating tsunami in March 2011. Cascadia “is capable of unleashing a similarly sized quake,” according to a release.

(MORE: Japan Tsunami: Deep-Sea Study Reveals Why It Was So Extreme)

Newman hopes to continue studying the Nicoya Peninsula’s response to the 2012 earthquake, which would allow seismologists to better understand how energy builds up again after an earthquake. The research helps to demonstrate the importance of taking such measurements in understanding where big earthquakes will strike next, he said. “All we need to do is make detailed images of how the Earth is deforming in subduction zones underwater,” he added, “and we can really start mapping out the areas that are building up energy for release in future earthquakes.”

The research was published in the journal Nature Geoscience.

MORE: The Deadliest Earthquakes of the Past 25 Years

India: Sept. 29, 1993

India: Sept. 29, 1993

The first of two of the top-10 deadliest earthquakes of the last 25 years that occurred in India was a 6.2 temblor that killed 9,748, according to the USGS. (DOUGLAS E. CURRAN/AFP/Getty Images)

  • India: Sept. 29, 1993
  • Turkey: Aug. 17, 1999
  • India: Jan. 26, 2001
  • Japan: March 11, 2011
  • Southeastern Iran: Dec. 26, 2003
  • Iran: June 20, 1990
  • Pakistan: Oct. 8, 2005
  • Eastern Sichuan, China: May 12, 2008
  • Northern Sumatra: Dec. 26, 2004
  • Haiti Earthquake: Jan. 12, 2010

Featured Blogs

96L Slowly Organizing on its Way to the Lesser Antilles

By Dr. Jeff Masters
August 20, 2014

A tropical wave (96L) located near 11°N 53°W, several hundred miles east of the Lesser Antilles Islands, is headed west-northwestwards at about 10 - 15 mph. Satellite loops on Wednesday morning showed the wave had a broad, elongated surface circulation and a modest amount of heavy thunderstorm activity that was steadily increasing in areal coverage and intensity. The storm was poorly organized, though, with a clumpy appearance and just a few low-level spiral bands.

July 2014 Global Weather Extremes Summary

By Christopher C. Burt
August 19, 2014

July was the 4th warmest such since 1880 according to NOAA and the 11th warmest according to NASA data (the difference in assessments is due to several factors which I’ll discuss in a future blog). It was unusually cool in the central portion of the U.S. while record warmth was observed in parts of the U.S. Northwest, Scandinavia and the Baltic nations. Several powerful typhoons made landfall in East Asia and Hurricane Arthur took a swipe at North Carolina.

Live Blog: Tracking Hurricane Arthur as it Approaches North Carolina Coast

By Shaun Tanner
July 3, 2014

This is a live blog set up to provide the latest coverage on Hurricane Arthur as it threatens the North Carolina Coast. Check back often to see what the latest is with Arthur. The most recent updates are at the top.

Tropical Terminology

By Stu Ostro
June 30, 2014

Here is some basic, fundamental terminology related to tropical cyclones. Rather than a comprehensive and/or technical glossary, this represents the essence of the meaning & importance of some key, frequently used terms.

2013-14 - An Interesting Winter From A to Z

By Tom Niziol
May 15, 2014

It was a very interesting winter across a good part of the nation from the Rockies through the Plains to the Northeast. Let's break down the most significant winter storms on a month by month basis.

What the 5th IPCC Assessment Doesn't Include

By Angela Fritz
September 27, 2013

Melting permafrost has the potential to release an additional 1.5 trillion tons of carbon into the atmosphere, and could increase our global average temperature by 1.5°F in addition to our day-to-day human emissions. However, this effect is not included in the IPCC report issued Friday morning, which means the estimates of how Earth's climate will change are likely on the conservative side.