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Elizabeth Kolbert has gone in search of the answer, and her short book, "Field Notes from a Catastrophe: Man, Nature, and Climate Change," is essential reading. Kolbert is a journalist (a writer for New Yorker magazine), not a scientist, and her aptly named "field notes" are reports from locations where important and telling climate science is taking place. She is an accomplished writer whose prose is deceptively simple and whose meaning is always clear. Climate change is complex stuff, but she deftly distills the brew to clarity. Hers is not only an "important" book, it is good reading, with revealing examples and piercing quotes from her subjects.
The climate is changing, and humankind is significantly responsible. These are facts no longer in question, Kolbert says. She cites a study by Naomi Oreskes, a professor at the University of California at San Diego, who reviewed more than 900 articles on climate change, and found that "not a single article disputed the premise that anthropogenic warming is under way." In the plain language of Marty Hoffer, professor of physics at New York University: "Right now, we're going to just burn everything up; we're going to heat the atmosphere to the temperature it was in the Cretaceous, when there were crocodiles at the poles."
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She reports on Arctic sea ice, which "has shrunk by roughly two hundred and fifty million acres, an area the size of New York, Georgia, and Texas combined." If you're inclined to doubt the statement, the book provides before and after images from NASA satellites. This change matters because sea ice is bright, and it reflects a high percentage of incoming sunlight, moderating global temperatures. Kolbert visits Greenland, a land covered by ice that, if melted, would be "enough water to raise sea levels worldwide by twenty-three feet."
Let's say for a moment that you don't believe Kolbert, the scientists, or the Inuits in Canada's Northwest Territories, who have begun to see a new bird for which their language has no word: the robin. You don't believe the mosquito researchers from the University of Oregon who were the first to "demonstrate that global warming had begun to drive evolution." Would you say we need more science before we do anything? Would you simply say, based on a short-term view of the matter, that the cost of addressing climate change is going to hurt our national economy?
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http://www.startribune.com/384/story/298126.html