Global warming: The end of skiing in Aspen? | AspenTimes.com

Global warming: The end of skiing in Aspen?

Runoff in the Roaring Fork River (shown here at the Woody Creek confluence) is projected to occur earlier in coming years, which would mean a shorter ski season. In this chart, the red line shows a simulated 2001 scenario, and the blue, green and purple lines show different future scenarios with different levels of global greenhouse gas emissions.

What’s Aspen got in common with Amarillo, Texas? Quite a bit, if global warming remains unchecked over the next century, according to a study commissioned by the city government.In the latest step in its Canary Initiative – a program designed to understand and reduce Aspen’s contribution to greenhouse gas production – scientists undertook what’s billed as an unprecedented look at the potential effects of global warming on a community’s climate.The study, titled “Climate Change and Aspen: An Assessment of Potential Impacts and Responses,” concluded that more precipitation will fall as rain rather than snow, higher temperatures will create drier conditions because the soil will absorb moisture more quickly, peak runoff will occur earlier, and minimum flows in streams will drop in summer and fall.”These things are really going to change our valley,” said John Katzenberger, director of the Aspen Global Change Institute and coordinator of the city’s report.Skiing, fishing and rafting – three linchpins of Aspen’s recreation industry – will be increasingly threatened by rising temperatures and drier conditions as the century progresses. Simply supplying enough water for a growing population could be a challenge, the study said.

Wildfires are expected to rage more intensely, and insects could proliferate in the national forest surrounding Aspen.Climbing temperatures will force alpine vegetation and wildlife to higher elevations, where the climate will be more compatible. Some species are “likely to become locally extinct,” the study said.Sitting in the hot seatIf humankind does nothing about global warming, if the planet’s population continues to grow at current rates, and industrialization continues to accelerate, Aspen’s average annual temperature will increase by as much as 14 degrees Fahrenheit by 2100, the study said. That would produce a climate similar to Amarillo’s today.Even if global warming is slowed, Aspen’s temperature will warm by 6 degrees by the end of the century, the study said. That would give it a climate more like Los Alamos, N.M.The alarming image painted by the study isn’t meant to make Aspenites surrender in despair, said Dan Richardson, the city’s global warming project manager. Instead it’s supposed to show them what’s at stake and, combined with an earlier study, spur action to reduce Aspen’s contribution to global warming. The earlier study, released in February, showed the major sources of Aspen’s greenhouse gases.”The first study asked what type of impact does Aspen have on global warming,” said Richardson. “This [study] asks what impact does global warming have on Aspen.”To find out the latter, 12 to 14 experts in fields including environmental science, economics, biology and climatology were enlisted to help with the yearlong study, said Katzenberger. A 12-member science advisory panel offered guidance and review. Three global climate models that are almost universally accepted in the scientific community were used to determine the effects on Aspen; the models range from a low-emissions future with slower warming to a high-emissions scenario with more drastic effects.

The study reached four key conclusions:• Aspen’s climate has already changed noticeably in the last 25 years. “Temperatures have increased by about 3 degrees and the average number of frost-free days per year has increased about 20 days,” the study said.• Total precipitation decreased 6 percent over the last 25 years while snowfall is down 16 percent.• Higher temperatures are inevitable even if the world’s nations make progress on global warming. Aspen’s temperature increases will range from 6 to 14 degrees by 2100, depending on how aggressive the response is to global warming.• Most of Aspen’s precipitation will fall as rain rather than snow. “Snowpack will decline, and peak runoff will occur earlier in the spring,” the study said. “Summer and fall stream flows will be reduced, potentially declining below the minimum needed to protect aquatic species. The greater the temperature rise, the more extreme these effects will be.”Katzenberger said he was unaware of any other study that examined climate change and its impacts on a specific community.Skiing follows silver mining?The study gave 10 examples of ecological effects that will result from the climate change. By midcentury, for example, “the vegetation in Aspen is likely to look more like what we now see near Basalt,” it said.

But the biggest change could shake Aspen’s soul as a ski town. The study boldly forecasts that if nothing is done about global warming, skiing will become to Aspen what silver mining is – a thing of the past. “Continued growth in global greenhouse emissions is projected to end skiing in Aspen by 2100 and possibly well before then,” said the study. “Reducing emissions could preserve skiing at middle and upper elevations.”In general, the ski season is likely to start later and end earlier,” the study continued. “Snow depths will be reduced. Spring melt will begin earlier. Higher temperatures will reduce snowmaking opportunities and increase competition for the needed water supplies.”Katzenberger said he hopes the study’s revelations demonstrate to Aspenites just what’s at stake over global warming and shakes people out of complacency.”It’s difficult to get your arms around a 100-year problem and do something about it,” he said.Richardson said the next step in the Canary Initiative is to propose specific steps to reduce Aspens’ greenhouse gas emissions. He is working on a draft “action plan” that will propose several different ways to achieve reductions. The draft plan will go to the City Council to see what actions they are willing to take.More information about the city’s Canary Initiative, including the recent study results, can be found at http://www.agci.org.Scott Condon’s e-mail address is scondon@aspentimes.com