I’ve seen plenty of good science reporting on the March 11 Tohoku earthquake-tsunami that double-whammied Japan last month, but the best I’ve seen so far is a straightforward, scientific account of the event in the March 22 issue of EOS, the weekly newspaper of the American Geophysical Union. (EOS has done a great job reporting the facts about Hurricane Katrina, Haiti’s latest earthquake, and many other contemporary and historic catastrophic events.)
The earthquake was “a plate boundary rupture along the Japan trench subduction zone,” according to EOS. Scientists estimate that the source area of the earthquake was 500-500 kilometers long with a maximum slip of 20 meters.
That’s a punch-in-the-gut description….
According to the International Tsunami Information Center (ITIC), the first tsunami wave hit the coast of northeastern Japan 15 minutes after the quake occurred. The ITIC received eyewitness reports of tsunami waves up to 13 meters high. The coast near Sendai “moved more than 4 meters horizontally and subsided about 0.8 meter.” A professor with the Earthquake Research Institute at the University of Tokyo told EOS that the tsunami may have flooded areas more than 5 kilometers inland.
Though I know we reside on a living planet, I find it hard to imagine such changes.
One scientist observed that while plate tectonics has been remodeling the surface of Earth for at least a billion years, likely longer, researchers have about 100 years worth of earthquake occurrence data to work with so far.
My take-home message is that we Earthlings should not be expecting precise earthquake predictions anytime soon. (We should also be ready for other unimaginable events, made worse by human crowding of coastal areas.)
Add to the challenge of limited data the politics of science. A U.S. Geological Survey official told EOS that it’s “difficult for those operating in political time to deal with events that are a blink of the eye in geologic but are not in the memory of even one’s grandparents.”
Everything clear now?