In a CNN commentary entitled Is the Earth Striking Back?, journalist and author Alan Weisman opines on the relationship between Anthropogenic Global Warming and a recent spate of powerful earthquakes:
As [the glaciers] flow off the land, we are warned, seas rise. Yet something else is lately worrying geologists: the likelihood that the Earth’s crust, relieved of so much formidable weight of ice borne for many thousands of years, has begun to stretch and rebound.
As it does, a volcano awakens in Iceland (with another, larger and adjacent to still-erupting Eyjafjallajokull, threatening to detonate next). The Earth shudders in Haiti. Then Chile. Then western China. Mexicali-Calexico. The Solomon Islands. Spain. New Guinea. And those are just the big ones, 6+ on the Richter scale, and just in 2010. And it’s only April. [Emphasis mine.]
Mr. Weisman, I challenge you to name just one reputable geologist who’ll admit to that “worry”.Alan Weisman is a journalist and author of the book The World Without Us, which is fodder for a TV show of the same name on one of those “bug channels” on the cable.
Yellow arrow: Iceland. Red circles: recent earthquakes blamed on melting glaciers.
First of all, the earth is big. Really, really big. The crustal plates that are being moved by the forces of plate tectonics are really big, too. The North American plate moves away from the Eurasian plate at a rate of a couple of centimeters per year. It takes an almost inconceivable amount of force acting over a really large area to move that much mass.
In scale, a glacier is not even a pimple on Mother Gaia’s backside. The Eyjafjallajokull glacier is about 8 miles E-W by 5 miles N-S.
Secondly, note that the recent earthquakes cited by Mr. Weisman are all in temperate or tropical zones. If the glaciers were directly causing disruption of the plates and plate boundaries, wouldn’t you think the earthquakes would occur first and worst near the sites of glacier loss?
Instead, the earthquakes occurred where they are supposed to occur, at plate boundaries. Most earthquakes and volcanic activity occurs at or near these plate boundaries, precisely because of the inexorable movement of the plates relative to each other, and the incredible buildup of energy at the plate margins.
Mr. Weisman’s commentary is particularly offensive because his title suggests a desire to anthropomorphize Mother Gaia while invoking unidentified geologists’ phantom-science opinions.
Oh, and one more thing: “…the Earth’s crust, relieved of so much formidable weight of ice borne for many thousands of years…” Mr. Weisman suffers, as do many scientific illiterates, that what we’ve experienced in our lifetimes is “normal”, and that any deviation from that familiar normalcy is, by definition, bad. This attitude is both ignorant and narcissistic.
However much of that “formidable weight” that you imagine to have vanished in the last 150 years, multiply it by about a billion and you’ve got an idea of what happened when the last ice age ended, rather suddenly and with no human assistance, about 13,000 years ago. That’s a blink of an eye in geologic terms. If glacial melting really did trigger earthquakes and volcanoes as you imagine, that effect would be ongoing today.
Cross-posted at VladEnBlog.