Aspen’s warm-weather woes
January 24, 2005
Heavy, wet “Sierra cement” snow conditions and shorter winters with smaller snowpacks might become typical for Aspen and other ski resorts in Colorado, according to one climate change researcher.But that could be the least of the state’s problems, said Stephen Saunders, founder and president of the Rocky Mountain Climate Organization in Denver. Reduced snowpacks and higher temperatures due to global warming could make it much tougher to live in a state that already struggles to store enough water to irrigate crops, run its industries and help its cities grow, he noted.Saunders will discuss how climate change could affect Colorado and what can be done about it in a lecture Thursday, Jan. 27, at the Aspen Center for Environmental Studies. Saunders, a former deputy assistant secretary of the U.S. Department of the Interior, has extensively researched temperatures and snowpacks in Colorado and parts of other states in the Upper Colorado River Basin. He said data shows that temperatures have already risen at a significant rate in the last decade and that snowpack levels just aren’t what they used to be. For example, the average annual temperature throughout the Upper Colorado River Basin was up 2.1 degrees for the five-year period from 2000 through 2004 compared to the historical average, according to Saunders. That’s in addition to an increase of 1.5 degrees from 1995 through 1999, he said.The baseline temperatures he used were established between 1895 and 1990.
Saunders isn’t predicting the average annual temperature will climb higher over the next five years. But he said it is clear the trend is for increasing temperatures. Research indicates temperatures will increase more during winter than summer, more at night than during the day, and more in the mountains than at lower elevations. That doesn’t bode well for places like Aspen and the unique environment of the Rocky Mountains.”We are particularly vulnerable to the effects of climate change,” Saunders said. Climate change models widely accepted in the scientific community indicate worldwide temperatures could increase between 3 and 10 degrees between 1990 and 2099, according to Saunders. The midpoint of that range is 5.4 degrees.”That’s enough of an increase to make Aspen’s average annual temperatures as warm as Durango’s,” he said. Durango’s temperatures would resemble Denver’s current climate, and Denver would resemble Richmond, Va.His research already indicates higher temperatures have reduced Colorado’s snowpack. Saunders uses snowpack measurements by the U.S. Natural Resources Conservation Service from 1961 to 1990 as his baseline.Using that 30-year baseline, snowpack levels have been down 12 of the last 16 years, he said.This year the statewide snowpack is about 20 percent above average, thanks to a wet first half of January. The jury won’t be in until after March, though. Last year, unseasonably high temperatures wiped out a deep snowpack – and emptied resorts – in March, he noted.
Saunders said there will still be winters with average and above average snow levels, but the data suggests they will be few and far between.He also cautioned that federal agencies use baseline data that might skew snowpack reports; they use 1971 through 2000 as their baseline. That period experienced higher temperatures, so snowpack averages were falling. In other words, that baseline data already reflects declining snowpacks.The one-two punch of lower snowpacks and hotter temperatures could make it harder to collect water in reservoirs in Colorado and bring greater evaporation rates, Saunders said.Of course Saunders is used to engaging skeptics on the topic of climate change. When asked if the 2.1-degree temperature increase in the last five years is just a freak occurrence, he acknowledged that climate and weather always change. But he said the changes experienced over the last decade are drastic and scientifically significant.”These are changes that are getting outside the realm of anything we’ve experienced or can reconstruct,” he said.He’s also used to skeptics’ claims that global warming is a natural occurrence. Natural events, by themselves, would have caused a warming in the worldwide average annual temperature prior to 1950, he responded. But natural events after 1950 would have produced cooler temperatures without humans’ activities, he said.
So Saunders is convinced that humans can slow global warming by reducing the amount of greenhouse gases they pump into the atmosphere.”We can reduce climate change. We can’t stop it,” he said.He formed the nonprofit Rocky Mountain Climate Organization to try to educate people about specific effects of climate change on Colorado and what can be done to combat it. The organization’s website is http://www.rockymountainclimate.org.Saunders’ presentation is at 7:30 p.m. Thursday at ACES. Admission is free for members. Nonmembers pay $3 for adults and $2 for children.Scott Condon’s e-mail address is email@example.com