(Unesp 2007)MELTDOWN: THE ALPS UNDER PRESSURE (Exc

(Unesp 2007)

MELTDOWN: THE ALPS UNDER PRESSURE (Excerpt 2)

"High-altitude regions seem to be more sensitive to the climate warming, and the retreat of glaciers is one sign," says Martin Beniston, a climate specialist at the University of Fribourg, Switzerland. "During Roman times it was even warmer than it is now. From Val-d'Isere to Zermatt, people could cross passes where they go glacier skiing now. But today it's the speed of warming that concerns us the most. It's very rapid." How rapid? Scientists estimate that the Alps have lost half their glacier ice in the past century, 20 percent of that since the 1980's; glaciers in Switzerland have lost a fifth of their surface area in the past 15 years.

As temperatures rise, so does the snow line. Sooner or later some ski centers will be stranded, and their towns will shrivel away. And rockfalls, only an occasional hazard in earlier times, are increasing, endangering communications towers and radio installations, not to mention the occasional human.

"What if there weren't any more skiing?" I asked Karin Thaler, a university student from Oberndorf, near Kitzbühel in Austria. She stared at me, thunderstruck. "That would be horrible," she stammered. "Everyone has something to do with skiing. A winter without tourists? It wouldn't be possible."

This is why the owners of the Pitztal ski resort and other sites are paying serious money to wrap their glaciers (some $121,000 a year for the Pitztal Glacier alone). They foresee a day when high-altitude glacier ski areas will be the only ones that can reasonably count on enough snow to stay open.

"We're businessmen," said Willi Krueger of the Pitztal resort, which sits above 9,000 feet. "If I were investing, I wouldn't invest in any ski area lower than 5,500 feet." Yet ski areas are still being developed throughout the Alps. And with them come roads, hotels, and ski lifts that can carry 1,800 people an hour.

Then there is the problem of snowfall. Global warming is making the snowfall less predictable. Sometimes there's a lot, sometimes too little, and it doesn't always come when you call it. Artificial snow is one of those solutions that just creates more problems. "If a resort wants people skiing in spring, it has to make the snow cover last longer," said Ulrike Petschacher of the World Wildlife Fund in Innsbruck. "But this damages the plants and disturbs the water cycle."

(By Erla Zwingle, National Geographic, February 2006.)

Indique a alternativa que preenche corretamente a sentença:

If the snow cover ............ longer, it ............ the plants and ............... the water cycle.