Agenda - 06-03-2008-5b5e - Laserfiche WebLink

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more methane, heating the Earth and seas further, and so on. There's 400 gigatons of methane locked in the ftozen arctic tundra - enough to start this chain reaction -and the kind of warming the Arctic Council predicts is sufFicient to melt the clathrates and release these greenhouse gases into the atmosphere. "Once triggered, this cycle could result in runaway global warming the likes of which even the most pessimistic doomsayers aren't talking about....Strong geologic evidence suggests something similar has happened at feast twice before. "The most recent of these catastrophes occurred about 55 million years ago in what geologists call the Paleocene-Eocene Thermal Maximum (PETM), when methane burps caused rapid warming and massive die-offs, disrupting the climate for more than 100,000 years. "The granddaddy of these catastrophes occurred 251 million years ago, at the end of the Permian period, when a series of methane burps came close to wiping out all life on Earth. "Mare than 94 percent of the marine species present in the fossil record disappeared suddenly as oxygen levels plummeted and life teetered on the verge of extinction....lt took 20 million to 30 million years for even rudimentary coral reefs to re-establish themselves and for forests to re-grow. In some areas, it took more than 100 million years for ecosystems to reach their former healthy diversity." In a more recent story about the acceleration of warming at the Arctic, Associated Press (AP) reporter Seth Borenstein wrote (Durham Herald Sun, "Scientists: `Arctic is Screaming,"' 12/12/07) "Alaska's frozen permafrost is warrr-ing, not quite thawing yet. But temperature measurements 66 feet deep in the frozen soil rose nearly four-tenths of a degree from 2006 to 2007, according to measurements from the University of Alaska. While that may not sound like much, "it's very significant," said University of Alaska professor Vladimir Romanovsky." This is an alarming message - I take it that way and intend for readers, developers & elected officials included, to take heed. And I am not the only one to recognize that global warming is a challenge to the very survival of the human species. John McPhee is a geologist who contributes regularly to TFie Neiv Yorker magazine. His work is scholarly, thoughtful, and well-grounded in science. March 12, 2007 he published "Season of the Chalk," a discourse on the geological history of the White Cliffs of Dover and the underlying strata of chalk that stretches eastward well into the European continent. McPhee writes of the Permian Extinction referred to in the Baltimore Sun article, and of the continuing scholarship and, speculation about how the Permian and other die-offs, including the demise of the dinosaurs, came about. He concludes this digression thus: "It's enough to ruffle conventional wisdom, unsettling the jury as to who killed whom and what killed what.~While the earth moves on toward the first mass extinction caused by a living species, debates about earlier ones are really unresolved." b) Rising ocean levels. It is no longer in dispute that this is happening, and that we'll see significant changes in the contours of the continents. Frvm Associated Press reporter Seth Borenstein, ("Rising seas could overtake lands...,"Durham Herald Sun 9/23/07): "In about a century, some of the places that make America what it is may be slowly erased. Global warming... is expected to cause oceans to rise by one meter, or about 39 inches. It will happen regardless of any future actions to curb greenhouse gases, several leading scientists say...