Sunday, March 13, 2011
Could the earthquake that triggered Japan's devastating tsunami be linked to climate change?
While it's unlikely that scientists will be able to provide a definitive answer anytime soon and Japan has long been a hotbed of seismic activity, past research suggests there may indeed be a link between climate change and earthquakes in some parts of the world.
Scientists have shown that weight shifts caused by melting glaciers can trigger tectonic activity. As ice melts and waters runs off, tremendous amounts of weight are lifted off Earth's crust. As the newly freed crust settles back to its original, pre-glacier shape, it can cause seismic plates to slip and stimulate volcanic activity, according to research into prehistoric earthquakes and volcanic activity.
Analyzing an 800,000-year record of volcanic activity in eastern California, Allen Glazner, a University of North Carolina-Chapel Hill geoscientist, found evidence that "peaks of volcanic activity occurred when ice was retreating globally," as told to the Wall Street Jorunal's Sharon Begley in 2006. "At first I thought it was crazy, but other scientists also found evidence that climate affects volcanism."
With Earth's glaciers and ice gaps melting at increasing rates due to climate change, it is conceivable that we could see further impact from "isostatic rebound" in the Earth's crust. Work by Patrick Wu, a professor of geophysics of the University of Calgary, suggests that past disappearance of ice "may still be contributing to quakes in eastern Canada." Read More
Polar Ice Sheets Adding Much More to Rising Seas than Previously Expected In the longest study to date of changes in polar ice sheet mass, researchers funded by NASA have found that the Greenland and Antarctic ice sheets are losing mass at a drastic and accelerating rate, contrary to the findings in 2007 of the United Nations Intergovernmental Panel on Climate Change. These findings suggest rather dramatically that the loss of ice into the oceans from ice sheets is soon going to overtake the loss of ice from Earth’s mountain glaciers as the largest contributor to global sea level rise a lot earlier than previous climate models had predicted...