As we go on pumping carbon dioxide into the air, we might borrow a line from
financial planners. Past performance is no guide to future results.
The buildup of carbon dioxide (CO2) is forcing scientists to rethink their
expectations - not only about the buildup of heat on Earth but also about the
implications for the natural world far beyond warming.
Take those powerful Alaskan earthquakes. We expect land to rise as the weight of
glaciers melts away. Should we also adjust our assessment of earthquake risk?
Two geophysicists say "yes." Glaciers hold down earthquake action even in a
seismically active region like Alaska, argue Jeanne Sauber with NASA's Goddard
Space Flight Center in Greenbelt, Md., and Bruce Molnia with the US Geological
Survey in Reston, Va. They use history and current data to make their case.
For example, earthquake action picked up in places where the ice masses
retreated some 10,000 years ago, Dr. Sauber notes. Scandinavia had major quakes
back then. Canada also had many moderate quakes as its glaciers melted.
Melting glaciers do not cause earthquakes: Quakes are created when forces within
the crust build ...