Posted on September 12, 2012 by Bob Berwyn
‘Warmer temperatures linked to human-caused climate change areplaying a role in drying out the region’
The stump of a beetle-killed ponderosa pine looms over the north rim of the Grand Canyon. Photo by Bob Berwyn.
By Summit Voice
FRISCO — Even just the small amount of global warming measured to-date has pushed climatic growing conditions to extremes, according to a new report from University of Arizona researchers.
“Our concern is that vegetation will experience even more extreme growing conditions as anticipated further warming exacerbates the impacts of future droughts,” said Jeremy Weiss, a senior research with UA’s department of geosciences. “We know the climate in the Southwest is getting warmer, but we wanted to investigate how the higher temperatures might interact with the highly variable precipitation typical of the region.”
The study found that warmer temperatures magnify drought conditions by making turning the atmosphere into a giant moisture-sucking sponge that make trees more susceptible to insects and other pathogens. The biggest impacts are in low to middle elevations, according to the study, scheduled for publication in the Journal of Geophysical Research Biogeosciences. (more…)
Filed under: climate and weather, Environment, forests, global warming | Tagged: climate change, drought, Forest health, forests, global warming, Southwest, Southwestern United States, University of Arizona | Leave a Comment »
Posted on April 8, 2012 by Bob Berwyn
Feds release public input on far-reaching supply and demand study
Business as usual won't cut it on the Colorado River, where demand has already exceeded supply the past 10 years or so.
By Summit Voice
SUMMIT COUNTY— Any way you slice it, the Colorado River simply can’t provide enough water on a regular basis to meet all the demands, ranging from municipal use to agriculture and sustaining healthy ecosystems for endangered native fish and non-native species important for recreation.
There may be water years — like 2010-2011 — when there’s an apparent surplus, at least for a short time, but that water goes into storage, primarily in Lake Powell, to buffer against future shortages. Even with last year’s bounty, Lake Powell didn’t come close to filling. While water managers may dream about a series of wet years, the reality is that in the long term, use of the river’s water will continue to exceed.
The only way to meet the demand is borrow against the river’s future by using stored water. This year, with snowpack in the key Upper Colorado Basin below 50 percent of average at the start of the runoff season, will be another one of those years when we go deeper into water debt. (more…)
Filed under: climate and weather, Colorado, Environment, rivers, water | Tagged: Colorado River, Lake Powell, Southwestern United States, water, western water supplies | Leave a Comment »
Posted on February 27, 2011 by Bob Berwyn
U.S. Geological Survey, UCLA study shows loss of vegetation in the Southwest will lead to more frequent and intense dust storms
Desert dust shows up in the snowpack at Loveland Pass, Colorado.
Dust storms like this one captured by a NASA satellite are predicted to get worse as global warming kills desert vegetation.
By Summit Voice
SUMMIT COUNTY — Desert dust blowing from the Southwest into the Rockies has been implicated in everything from earlier snowmelt and air quality violations to causing avalanches.
A new study shows the storms more frequent and intense as global warming kills desert vegetation.
A research team from the U.S. Geological Survey and UCLA looked at climate, vegetation and soil measurements collected over a 20-year period in Arches and Canyonlands National Parks in southeastern Utah. Long-term data indicated that perennial vegetation in grasslands and some shrublands declined with temperature increases. The study then used these soil and vegetation measurements in a model to project future wind erosion. (more…)
Filed under: air quality, climate and weather, Colorado, Environment, global warming, Summit County news | Tagged: Colorado Plateau, desert dust storms, Environment, global warming, Proceedings of the National Academy of Sciences, Southwestern United States, Summit County News, United States Geological Survey, University of California Los Angeles | 1 Comment »
Posted on January 3, 2011 by Bob Berwyn
A NASA satellite image of the desert Southwest.
Current dry spell matches some of the most severe conditions on record
By Summit Voice
SUMMIT COUNTY — With Colorado River flows at Lees Ferry during the past 10 years registering the lowest levels ever in the historic record, University of Arizona researchers say the Southwest could already be in the midst of a major dry spell comparable to the 12th century drought that drove the Anasazi from the Four Corners region.
Their conclusion is based on a review of previous studies that document the region’s past temperatures and droughts.
“Major 20th century droughts pale in comparison to droughts documented in paleoclimatic records over the past two millennia,” the researchers wrote.
By figuring out when and for how long drought and warm temperatures coincided in the past, the team identified plausible worst-case scenarios for the future. Such scenarios can help water and other resource managers plan for the future, the team wrote. (more…)
Filed under: climate and weather, Colorado, global warming, Summit County Colorado | Tagged: Colorado River, drought, Lamont–Doherty Earth Observatory, Lees Ferry, Proceedings of the National Academy of Sciences, river flows, Southwest, Southwestern United States, Summit County Colorado, Summit County News | Leave a Comment »