Previous Page View
Printer FriendlyReprinted with permission from Popular
Science, August 1999.
© Copyright, Times Mirror Magazines, Inc.
Warming Is Global, Change Is Local
LOUSY SKIING and bad apples. That's what Pacific Northwest residents may be able to expect in 80 or so years.
While global warming usually is depicted as a fairly simple event-fewer cold snaps in the winter, a few more 100-plus-degree days in July-its regional implications could be far more dramatic. That's what climate researcher Ruby Leung of the Pacific Northwest National Laboratory in Richland, Washington, found when she ran finely calibrated computer models to study the impact of a warmer climate on Oregon and Washington. Her conclusion: Precipitation that now falls in the mountains as snow from late November through late March will turn into rain, raising the average snowline from today's 3,000 feet to 4,100 feet.
That will turn now-popular ski resorts in the central Cascade Mountains into miserable aqua-parks. It will wreak havoc on farmers on the dry east side of the range who rely on spring and summer snowmelt to irrigate their apples and wheat. And flooding-now common in November when storms wash ashore-could be severe throughout the winter.
Of course, what makes climate so maddeningly difficult to predict are the natural variations that blur the big picture. The Northwest, for instance, may now be leaving a 20-year period of relatively warm, dry weather and entering an equally long period of cool, wet weather. The cause? A poorly understood event called the Pacific Decadal Oscillation, a slow-changing climatic episode apparently related to large pools of cool or warm water in the Pacific Ocean. During the winter of 1998-'99, for instance, ski resorts in Washington State were so overwhelmed by record snows that some had to close simply to dig out chair lifts.-D.G
 |
 |
 |
