It seems like there are more big earthquakes than ever before.
Alter the climate, set off earthquakes, volcanoes remotely through the use of electromagnetic waves.
Secretary Cohen might be right. Does that mean that hostile governments or terrorists are using electromagnetic weapons to cause earthquakes?
Others claim that climate change or an approaching celestial event having to do with the year 2012 are causing the earthquakes. Are they right?
Well, the United States Geological Survey explains that – contrary to appearances – we really don’t have more earthquakes than normal:
Although it may seem that we are having more earthquakes, earthquakes of magnitude 7.0 or greater have remained fairly constant throughout this century and, according to our records, have actually seemed to decrease in recent years.
There are several reasons for the perception that the number of earthquakes, in general, and particularly destructive earthquakes is increasing.
1) A partial explanation may lie in the fact that in the last twenty years, we have definitely had an increase in the number of earthquakes we have been able to locate each year. This is because of the tremendous increase in the number of seismograph stations in the world and the many improvements in global communications.
2) The population at risk is increasing. While the number of large earthquakes is fairly constant, population density in earthquake-prone areas is constantly increasing. In some countries, the new construction that comes with population growth has better earthquake resistance; but in many it does not. So we are now seeing increasing casualties from the same sized earthquakes.
3) Better global communication. Just a few decades ago, if several hundred people were killed by an earthquake in Indonesia or eastern China, for example, the media in the rest of the world would not know about it until several days, to weeks, later, long after such an event would be deemed “newsworthy”. So by the time this information was available, it would probably be relegated to the back pages of the newspaper, if at all. And the public Internet didn’t even exist. We are now getting this information almost immediately.
4) Earthquake clustering and human psychology. While the average number of large earthquakes per year is fairly constant, earthquakes occur in clusters. This is predicted by various statistical models, and does not imply that earthquakes that are distant in location, but close in time, are causally related. But when such clusters occur, especially when they are widely reported in the media, they are noticed. However, during the equally anomalous periods during which no destructive earthquakes occur, no one deems this as remarkable.
The USGS provides the following charts on large earthquakes (click here to see full images):
This article was posted: Wednesday, April 7, 2010 at 4:29 am