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- <text id=93TT0267>
- <link 93TO0113>
- <title>
- July 26, 1993: If You Think The Weather Is Bad...
- </title>
- <history>
- TIME--The Weekly Newsmagazine--1993
- July 26, 1993 The Flood Of '93
- </history>
- <article>
- <source>Time Magazine</source>
- <hdr>
- COVER, Page 33
- DISASTERS
- If You Think The Weather Is Bad...
-
- </hdr>
- <body>
- <p> Weather is almost impossible to predict more than a week or
- two in advance. But when it comes to climate--the long-term
- weather averages that make the U.S. temperate and the tropics
- torrid--scientists are confident that they understand the
- overall pattern. Over the past million years or so, the planet
- has swung between ice ages lasting on the order of 100,000 years
- and interglacial periods of about 10,000. During each phase,
- the climate is pretty steady. It's the stability of the current
- interglacial epoch, which began 10,000 years ago, that made
- the invention of agriculture, and thus the rise of civilization,
- possible.
- </p>
- <p> Now it looks as though the concept of long-term stability may
- be wrong. According to two articles in last week's Nature, deep
- holes drilled into the ancient ice of Greenland have brought
- up evidence of sudden, dramatic swings in climate during the
- last interglacial period, about 120,000 years ago. Several times,
- average global temperatures dropped as much as 25 degreesF,
- plunging the planet back into ice-age conditions, and stayed
- there for tens or hundreds of years before recovering. And the
- changes happened not over centuries, as scientists would have
- predicted, but in as little as a decade. The tranquillity of
- recent centuries may be a climatic fluke.
- </p>
- <p> The discovery, says British scientist David Peel, co-author
- of one of the reports, is "staggering." Worldwide temperature
- shifts of a few degrees over half a century--the kind envisioned
- in theories of global warming--would disrupt weather patterns,
- change sea levels and be difficult for animal and plant life
- to adjust to. The changes Peel measured, though, are roughly
- three times as severe and rapid.
- </p>
- <p> One ominous sign: normal temperatures during the last interglacial
- epoch were about 4 degreesF warmer than they are this time around,
- and levels of carbon dioxide in the atmosphere were significantly
- higher. As humans pump more and more CO2 into the air and temperatures
- rise, the planet will approach the state it was in back then.
- And if those conditions tend to be inherently unstable--an
- idea scientists consider plausible--people may someday look
- back on the early 1990s as an idyllic time when the weather
- was benign.
- </p>
- <p> By Michael D. Lemonick. Reported by Barry Hillenbrand/London
- </p>
-
- </body>
- </article>
- </text>
-
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