Do earthquakes give off warning signals?

A tsunami survivor, left, looking for belongings from where her house was standing walks by U.S. rescue team members with a sniff dog working in debris in Ofunato in Iwate Prefecture (state), northeastern Japan, Tuesday, March 15, 2011, four days after a massive earthquake and tsunami slammed northeastern Japan. (AP Photo/Yomiuri Shimbun, Masamichi Genkoh)

May 20, 2011 8:31:56 PM PDT
A team of NASA and Russian scientists thinks it's found a way to predict earthquakes. If it works, it could save a lot of lives. However, not all earthquake scientists agree with these findings.

The March 11 earthquake in Japan was a magnitude 9.1. A team of scientists monitoring quakes there say they could tell it was coming because the atmosphere above the epicenter was heating up from eight days before.

Russian scientist Dimitar Ouzounov says stresses on the Earth's crust leading up to a quake cause gases like radon to escape into the atmosphere -- 100 miles above the Earth they ionize and create heat that is detectable by satellites. Ouzounov's team says out of 24 quakes in Japan of magnitude 7 or greater, all showed the same atmospheric signals beforehand.

"His interpretation from my perspective is not the last word," says NASA Ames scientist and researcher Friedemann Freund, who agrees the atmosphere heats up, but not from escaped gases. He thinks as stresses on the Earth's crust build toward a quake, massive air ionization is a measurable result. But still, he cautions prediction is too strong a word.

"We will never be able to predict," he says. "We can forecast, like the weather service forecasts certain weather conditions, and the reason is whatever we do we can only detect the stress buildup in the Earth, not the earthquake itself."

"We've also learned a lot about the physics of failure of the Earth's crust and it is not reassuring," says USGS geophysicist Malcom Johnston, who believes quake precursors happen at such tiny places on a fault, it's impossible to know for sure what's coming. However, he says it's important to keep looking. "We are very honest about what does work and what doesn't work."

The NASA Russian team's data on the 24 Japan quakes will be released late this year.