by Matt Owens January 5, 2013
What happens if your friend sits on one end of a water bed and you jump on the other end? Rapid weight redistribution. So what happens inside the Earth when ice sheets melt/slide off continents, and sea levels rise?
The added weight of rising seas puts more pressure on the tectonic plates beneath the oceans while releasing pressure from continental plates and leads to increased volcanic activity, of course. The water bed analogy is a bit exaggerated because ice sheets won't actually jump into the oceans. Analogies aside, the process is more complex in its actual mechanics, and involves changes in stress levels through the crust layers which in turn changes the rate at which magma rises. Such are the findings of a recent study.
One possibly hopeful note from the new research is that in the past there was a lag of several thousand years between the period when sea levels rose quickly and when volcanic activity increased. "Possibly," because volcanoes can put global warming on hold by releasing reflective aerosols high into the air (such was the case with the Mt. Pinatubo eruption that caused a pronounced global cooling influence for several years). On the other hand, excessive cooling from volcanoes can trigger global crop failures.
Either way, the current rate of warming might challenge past relationships because we are warming the planet so fast at present. If the ice caps melt faster than they ever have before, the thousands of years time lag could be put to the test.
The research was conducted by a German and American based team of scientist, led by Steffen Kutterolf. It appeared in the on-line November issue of the Journal Geology.