Posted on November 22, 2013 by Bob Berwyn
NOAA’s winter outlook offers little relief for Arizona, New Mexico
By Bob Berwyn
FRISCO — Drought conditions may persist across the southwestern U.S. this winter and may redevelop across the Southeast, according to the seasonal outlook from NOAA’s Climate Prediction Center.
“Even though we don’t have La Niña, the atmosphere across the Pacific seems to be stuck in a La Niña mode … It’s been quite surprising to us, how persistent the pattern is,” said Mike Halpert, acting director of the Climate Prediction Center.
Parts of the Southwest, especially New Mexico, have been experiencing one of the driest periods on record, and Halpert said there is “decent agreement” in the CPC’s models on the climate signal that has resulted in the persistent trend. Continue reading
Filed under: climate and weather, Drought, El Niño, La Niña | Tagged: climate, Climate Prediction Center, drought, El Nino, ENSO, La Niña, Southwest, winter weather outlook | 2 Comments »
Posted on November 16, 2013 by Bob Berwyn
2013 brought record levels of dust to Colorado’s mountains
More frequent desert dust storms dropping pollution on the Rocky Mountain snowpack is one of the climate change impacts affecting the Colorado high country.
By Bob Berwyn
FRISCO — Dust storms that darken the Rocky Mountain snowpack and speed snowmelt are becoming more extreme, according to new research. Particularly heavy dust-on-snow events can speed the melt-out of the snowpack by a full six weeks, all other factors being equal, said Jeffrey Deems, a researcher with the Western Water Assessment and the National Snow and Ice Data Center.
“In 2006 we were impressed at how much dust there was. Then 2009 turned up, and 2010, and 2013 was the dustiest year we’ve recorded in the San Juans,” Deems said, explaining that the latest study, put together by researchers with NOAA’s Cooperative Institute for Research in Environmental Sciences was aimed at updating previous work with data from those heavy dust years.
Last spring, on April 8, a single 16-hour dust storm dropped more dust on the San Juans than the annual totals in any previous winter since scientists started taking detailed measurements, said Chris Landry, director of the Center for Snow and Avalanche Studies in Silverton, which tracks the dust-on-snow events via a network of observation sites. Continue reading
Filed under: climate and weather, Colorado, Drought, snow | Tagged: Colorado, Colorado River Basin, drought, dust on snow, Environment, global warming, water | 1 Comment »
Posted on November 15, 2013 by Bob Berwyn
California’s redwood forests recycle ocean fog to create their own microclimate. bberwyn photo.
Amazon rainforest may be more resilient than previously believed
By Summit Voice
FRISCO — As one of the Earth’s big lungs, the fate of the Amazon rainforest in the face of global warming is a critical climate question. New research suggests that, with strong conservation measures in place, the rainforest may be more able to cope with dry conditions than projected by other studies.
Many climate models over-predict the water stress plants feel during the dry season because they don’t take into account the moisture that the forest itself can recycle in times of drought. In this study, published in the Journal of Climate, the researchers removed unrealistic water stress from their model and found that the moisture that is recycled by the forest is sufficient to reduce the intensity of drought conditions. Continue reading
Filed under: climate and weather, Drought, Environment, forests | Tagged: Amazon Rainforest, climate, drought, forests | Leave a comment »
Posted on November 13, 2013 by Bob Berwyn
Agency releases draft versions of climate adaptation implementation plans for review and public comment
The EPA says the Rocky Mountain region is particularly vulnerable to water supply issues as a result of global warming.
By Summit Voice
FRISCO — The climate in the Rocky Mountains is changing rapidly, outside the range to which society has adapted in the past, according to the EPA’s draft climate adaptation implementation plan for the agency’s Southwest Region, which covers western Colorado.
Most of the “cascading effects” of global climate change will be felt in the region, including increased air temperature, decreased precipitation in some areas, and more severe storms. Along the West Coast, oceans will become more acidic and warm and sea level will rise. Continue reading
Filed under: climate and weather, Drought, Environment, global warming, rivers, water | Tagged: climate, climate change adaptation, Environment, EPA, global warming, Rocky Mountains | 2 Comments »
Posted on November 10, 2013 by Bob Berwyn
Agency cites increases of extreme weather, drought and flooding in call for public comment
A NASA map shows global temperature anomalies for Aug. 2013.
By Summit Voice
FRISCO — At this point, most people know that global warming is already having tangible impacts on their day-to-day lives, from more intense heatwaves to destructive coastal flooding and longer wildfire seasons.
But it’s not always easy to figure what, if anything, can be done. To help communities in different parts of the country, the EPA is developing climate change adaptation implementation plans, with detailed information about the actions EPA plans to take across the country to help communities adapt to a changing climate. Continue reading
Filed under: climate and weather, Drought, extreme weather, global warming | Tagged: Barack Obama, Climate Action Plan, climate change, climate change adaptation, EPA, global warming | Leave a comment »
Posted on November 8, 2013 by Bob Berwyn
Shifts in precipitation patterns would have big consequences for agriculture, forests and municipal water supplies
Research suggests that deforestation will likely produce a weather cycle over the Amazon consisting of abnormally dry air in the sun-scorched northern Amazon around the equator weighted by wetter air in the cooler south (left). The Princeton-led researchers found that the Amazon pattern would be subject to meandering high-altitude winds known as Rossby waves that move east or west across the planet (center). The Rossby waves would move the dry end of the Amazon pattern directly over the western United States from December to February, while the pattern’s rainy portion would be over the Pacific Ocean south of Mexico (right). Image courtesy Princeton University.
By Summit Voice
FRISCO — Continued deforestation in the Amazon region could have significant impacts on the weather in North America, according to Princeton researchers, who used fine-grained climate models to simulate how precipitation patterns could shift in the future.
Their findings suggest that total deforestation of the Amazon may significantly reduce rain and snowfall in the western United States — specifically, 20 percent less rain for the coastal Northwest and a 50 percent reduction in the Sierra Nevada snowpack, a crucial source of water for cities and farms in California.
“The big point is that Amazon deforestation will not only affect the Amazon — it will not be contained. It will hit the atmosphere and the atmosphere will carry those responses,” said lead author David Medvigy, an assistant professor of geosciences at Princeton. Continue reading
Filed under: climate and weather, Drought, El Niño, Snow and weather | Tagged: Amazon Rainforest, climate, drought, El Nino, western U.S. | 1 Comment »
Posted on November 3, 2013 by Bob Berwyn
High flow experiment planned for early November to restore aquatic and riparian Colorado River ecosystems downstream of Glen Canyon Dam
By Summit Voice
FRISCO — Even with some bonus inflow in September, the past water year Oct 1, 2012 – Sept. 30, 2013) ended up as the fourth-driest on record for the Colorado River Basin as measured at Lake Powell — the key reservoir on the river that helps balance supply and demand between the upper and lower basins.
Overall water storage in the Colorado River Basin in the last 14 years has ranged from a high of 94 percent of capacity in 2000 to the present low of 50 percent at the start of the 2014 water year.
Filed under: climate and weather, Colorado, Colorado River, Drought, Environment, global warming, rivers, water | Tagged: climate change, Colorado River, drought, Lake Powell, water storage | 1 Comment »
Posted on October 22, 2013 by Bob Berwyn
New study says IPCC projections are too conservative
By Summit Voice
FRISCO — In a classic case of climate disruption, research shows that the dry season in southern Amazonia has lengthened by about one week per decade since 1979. Parts of the region may not be able to support rainforest vegetation much longer. A big forest die-back could trigger the release of large volumes of the greenhouse gas carbon dioxide into the atmosphere, a team of scientists warned this week.
The changes could disrupt plant and animal communities in one of the regions of highest biodiversity in the world, said University of Texas professor Rong Fu, who led the team of scientists. Continue reading
Filed under: climate and weather, Drought, Environment, global warming, greenhouse gases | Tagged: Amazon Rainforest, Climate disruption, global warming, Intergovernmental Panel on Climate Change, IPCC | Leave a comment »
Posted on October 13, 2013 by Bob Berwyn
Long-term climate shifts linked with historic spruce beetle episodes in Colorado
A Colorado spruce forest near Shrine Pass, Colorado.
Spruce beetles are spreading rapidly and killing trees in the southern Rockies.
By Summit Voice
FRISCO — The current spruce beetle outbreak in Colorado’s high country has the potential to grow larger in scope than the recent mountain pine beetle epidemic that killed mature lodgepole pines across millions of acres.
And the trigger of for the spruce beetles is drought that’s linked with long-term changes in sea-surface temperatures in the Northern Atlantic Ocean, a trend that is expected to continue for decades, according to a new study by scientists with the University of Colorado, Boulder.
The new study is important because it shows that drought is a better predictor of spruce beetle outbreaks in northern Colorado than temperature alone, said Sarah Hart, a CU-Boulder doctoral student in geography. Continue reading
Filed under: climate and weather, Colorado, Drought, Environment, Forest health, forests | Tagged: Atlantic Multidecadal Oscillation, climate, Colorado, Forest health, forests, southern rockies, spruce beetles | 2 Comments »
Posted on September 3, 2013 by Bob Berwyn
North American spring-season snow cover extent has declined steadily in recent decades, according to measurements from the Rutgers Global Snow Lab.
‘Shrinking in supply, growing in demand’
By Summit Voice
FRISCO — Since the 1980s, warmer spring temperatures in the Rocky Mountain region have been melting the snowpack earlier, with increasing temperatures tabbed as the main factor in the decline, according to the U.S. Geological Survey.
The agency carefully tracks streamflows and snowpack measurements, with decades of data now showing clear trends toward shorter winters, earlier spring runoff and an overall 20 percent shrinkage of the snowpack in the mountains of the western U.S.
The researchers say at least part of the changes are due to global warming caused by heat-trapping greenhouse gases, but that natural variability is also a factor. Regardless of the exact cause, the snowpack decline is already causing major headaches for water managers in the region facing dwindling supplies and increased demand.
The Colorado River Water Conservation District will focus on some of the emerging critical water questions during its annual water seminar (Sept. 13, 9 a.m. to 3:30 p.m.) in Grand Junction. USGS researcher Greg Pederson, who is the lead author on some of the key snowpack studies, will discuss how spring is killing the Rocky Mountain snowpack, especially at lower elevations, where the effects of warmer temperatures are more pronounced. Continue reading
Filed under: climate and weather, Colorado, Colorado River, Drought, global warming, rivers, water | Tagged: Rocky Mountain snowpack, The West, United States Bureau of Reclamation, United States Geological Survey | Leave a comment »