Changes seen for spring runoff
By Bobby Magill , The Daily Sentinel
Published January 25, 2008 at 12:30 a.m.
Snow and cold weather might make it seem like climate change doesn't affect Colorado, but a U.S. Geological Survey scientist says that the state's runoff season will see dramatic mood swings in coming decades.
David Clow of the USGS told members of the Colorado Water Congress on Thursday that global warming doesn't yet seem to be affecting Colorado's snowpack dramatically, but that runoff already occurs two weeks earlier than it did 27 years ago.
By the end of the century, runoff could come a full month earlier than it will this year, he said.
The USGS studied snowmelt timing at all 72 U.S. Natural Resources Conservation Service snow-monitoring sites across the state. They found that in 1980, snowmelt occurred two weeks later than it has in recent years.
Springtime air temperatures determine when snow melts in Colorado. "When you have warm conditions, you'll have earlier snowmelt," Clow said.
With average global temperatures expected to rise between three and nine degrees by 2100 and the rate of global warming expected to increase, an earlier snowmelt season is sure to come, he said.
Clow said that scientists don't know exactly how climate change will affect temperatures in Colorado, but that they do know temperatures will increase more dramatically in the middle of large land masses, such as North America.
Featured
-
DNC in Denver
Complete coverage of the 2008 Democratic National Convention.
-
The Crevasse
A five-part series that examines one tragic day on Mount Rainier.
-
Deadly denial
Sick nuclear workers applied for government compensation but most haven't seen a dime.
-
Final Salute
The Rocky followed Maj. Steve Beck as he took on the most difficult duty of his career.
-
'Colorado's burning'
Coverage of the state's worst wildfires.
-
Columbine shootings
Coverage of the April 20, 1999, shootings at Littleton's Columbine High School.
-
The Crossing
Colorado's deadliest traffic accident killed 20 children on Dec. 14, 1961.
-
Osveli's journey
Osveli Sales left Guatemala for a better life. Two months later, he came home in a box.
-
Wake for an Indian warrior
Oglala Sioux bestow a tribute to the first tribal fatality in Iraq.


January 25, 2008
noon
Suggest removal
fmikey writes:
Does snowmelt registered in only one previous year, 1980, constitute conclusive proof that snowmelt is now starting earlier than in previous years, as seems to be the implication here? It would seem a few more years around 1980 should be included in the mix, to see if they support the 1980 figures, and thus a generally later snowmelt at that time than this.
This data, if it is as represented, is incomplete and represents a sloppy investigation and questionable conclusion. On the other hand, we wonder if we are getting a complete story from the media....
January 25, 2008
7:35 p.m.
Suggest removal
dwclow writes:
In their presentation, the USGS stated that they used data from all 27 years of validated data available at the time of the analysis. The statistical method that was used was the Regional Kendall Trend test, which is described by the USGS in a peer-reviewed journal article (http://pubs.acs.org/cgi-bin/abstract....).