Tuesday, June 26, 2007

The Real Global Warming

Everyone gets taught that the interior of the planet is really hot - molten rock flowing out of volcanoes - hot. At least one geologist stops looking for oil long enough to contemplate what the superheated inferno below our feet might mean to the land we are standing on.
Earth's inner heat keeps cities afloat: In what they said was the first calculation of its kind, the researchers said heat inside the planet accounts for half the reason land rises above sea level or higher to form mountains. ... "Researchers have failed to appreciate how heat makes rock in the continental crust and upper mantle expand to become less dense and more buoyant," said Derrick Hasterok, a graduate student in geology and geophysics.
Plate tectonics emerges as a theory in the 1960’s to explain the horizontal drift of the earths land masses. This new line of thought may improve our understanding of the planet's surface features by more completely explaining the vertical motions of the crust.
Derrick Hasterok: Causes of Continental Elevation - Elevation of the continents varies widely from below sea level by nearly a kilometer on the continental shelves to the height of Mt. Everest above 9 km. Regional elevation variations can be separated into three separate contributing factors. 1: Variations in composition (density) and crustal thickness. 2: Steady-state thermal expansion due to heat content. And 3: Dynamic elevation resulting from mantle and surface processes and plate tectonics. My work involves quantifying the contributions of each of these factors to the continents.
I have to admit the popular press did grab my interest by sensationalizing the story with the line: “New York would drop to 1,427 feet below the Atlantic ocean, Boston and Miami even deeper. Los Angeles would rest 3,756 feet below the surface of the Pacific ocean”. Some one ask Al Gore if he can use his power to control nature to save our coastal cities from flooding, by simply turning up the heat beneath them.