文档介绍：最新雅思阅读20篇
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I will persist until I succeed!
http:emperature affect the arrival of spring, allowing ecologists to make improved predictions about the impact of climate change. A small band of researchers is combing through hundreds of years of records taken by thousands of amateur naturalists. And more systematic projects have also started up, producing an overwhelming response. “The amou
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I will persist until I succeed!
nt of interest is almost frightening,” says Sparks, a climate researcher at the Centre for Ecology and Hydrology in Monks Wood, Cambridgeshire.
C Sparks first became aware of the army of “closet phenologists”, as he describes them, when a retiring colleague gave him the Marsham records. He now spends much of his time following leads from one historical data set to another. As news of his quest spreads, people tip him off to other historical records, and more amateur phenologists come out of their closets. The British devotion to recording and collecting makes his job easier- one man from Kent sent him 30 years’ worth of kitchen calendars, on which he has noted the date that his neighbour’s magnolia tree flowered.
D Other researchers have unearthed data from equally odd sources. Rafe Sagarin, an ecologist at Stanford University in California, recently studied records of a betting contest in which participants attempt to guess the exact time at which a specially erected wooden tripod will fall through the surface of a thawing river. The competition has taken place annually on the Tenana River in Alaska since 1917, and analysis of the results showed that the thaw now arrives five years earlier than it did when the contest began.
E Overall, such records have helped to show that, compared with 20years ago, a raft of natural events now occur earlier across much of the northern hemisphere, from the opening of leaves to the r