WHAT I DIDN’T KNOW ABOUT EARTHQUAKES.

WHAT I DIDN’T KNOW ABOUT EARTHQUAKES. I reacted to the discovery that not assigning hurricane status to a storm can mislead somebody like me in part because of something I just read in Nate Silver’s THE SIGNAL AND THE NOISE: Why So Many Predictions Fail—but Some Don’t. Nick lent it to me and I am currently absorbed by it. Silver has a chapter on the problems in forecasting earthquakes. In the course of discussing forecasting, he points out that the Richter scale, which is used in reporting on earthquakes as well as for scientific purposes, is a logarithmic scale. Further, “a one-point increase in the scale indicates that the energy release has multiplied by thirty-two.” For example, the earthquake in L’Aquila, Italy in 2009 had a magnitude of 6.3. The earthquake in Japan in 2011, which had a measured magnitude of 9.0 or 9.1, was almost 11,000 (!) times more powerful. To repeat, an earthquake of magnitude 9.1 is about 11.000 times more powerful than an earthquake of magnitude 6.3. I had no idea.