Posted on November 19, 2014 by Bob Berwyn
Most of the world’s ice rivers are shrinking into oblivion
The Dachstein Glacier in Austria has visibly and dramatically decreased in size in just a couple of decades. bberwyn photo.
By Summit Voice
FRISCO — For mountain dwellers around the world, shrinking glaciers are one of the most vivid symptoms of Earth’s rising fever. Those gleaming mantles of ice have already disappeared from iconic landscapes like Glacier National Park.
Globally, millions of people rely on glacier-regulated stream flows for water supplies, so communities need to prepare for disruptions in the hydrological cycle because it’s becoming increasingly apparent that the meltdown is not going to stop. Continue reading
Filed under: climate and weather, global warming | Tagged: CIRES, glaciers, global warming, National Snow and Ice Data Center | Leave a comment »
Posted on October 22, 2014 by Bob Berwyn
Study hints at complexity of forecasting climate change in the mountains
FRISCO — Teasing localized climate information from global models is tough at any level, and becomes even harder when you factor in the complexities of mountain topography and highly localized and seasonal weather patterns.
But new data has enabled scientists to better understand the long-vexing climate change puzzle of growing glaciers in the Karakoram mountains, a northern range of the greater Himalayas. Understanding the future of glaciers in that region, and around the world, has implications for millions of people who rely on the glaciers for water supplies.
Most glaciers in the Himalayas and around the world have been retreated for the past 150 years, and the melting has accelerated in the last few decades. But the Karakoram glaciers have been stable or growing. The new study says it’s because a unique and localized seasonal pattern keeps the mountain range relatively cold and dry during the summer. Continue reading
Filed under: climate and weather, global warming | Tagged: climate modeling, glaciers, global warming, growing glaciers, Karakoram Mountains, mountain climate change | Leave a comment »
Posted on August 18, 2014 by Bob Berwyn
‘In our data we find unambiguous evidence of anthropogenic contribution to glacier mass loss’
Shrinking glaciers on the Dachstein Mountains in Austria will affect water supplies far downstream in local areas and in distant rivers. bberwyn photo.
FRISCO — Some of the world’s glaciers were shrinking before the onset of unchecked heat-trapping pollution, but the human factor in the glacial equation has grown exponentially in the past few decades.
A new modeling study led by scientists at the University of Innsbruck (Austria) shows that only about 25 percent of the global glacier mass loss during the period of 1851 to 2010 is attributable to anthropogenic causes. However, between 1991 and 2010 the fraction increased to about two-thirds.
“In the 19th and first half of 20th century we observed that glacier mass loss attributable to human activity is hardly noticeable but since then has steadily increased,” said researcher Ben Marzeion, explaining that scaled-down regional models can detect an anthropogenic influence in America and the Alps, where glacier changes are particularly well documented. Continue reading
Filed under: climate and weather, Environment | Tagged: climate, Environment, glaciers, global warming, greenhouse gases, mountains, water | Leave a comment »
Posted on May 9, 2014 by Bob Berwyn
The world’s glaciers are dwindling.
CU Boulder scientists help lead mapping effort
FRISCO — Lots of quibbling over the exact rate and pace of glacier melt has at least partly obscured the grim reality that many of the world’s glaciated regions will see profound changes in the next few decades as global temperatures continue to rise.
That meltdown will raise sea level, but so far, nobody has been able to quantify the amount precisely. But new data gathered in a study led by University of Colorado, Boulder scientists should help. The team, including researchers from Trent University in Ontario, Canada recently completed the first mapping of virtually all of the world’s glaciers. That enables calculations of their volumes and ongoing contributions to global sea rise as the world warms. Continue reading
Filed under: climate and weather, global warming | Tagged: CU Boulder, Environment, glaciers, sea level rise | 1 Comment »
Posted on February 26, 2014 by Bob Berwyn
Temps, not snowfall, drive shrinkage of Peru’s Quelccaya Ice Cap
By Summit Voice
FRISCO — Geologists are getting better at unraveling the mysteries of historic glacial episodes, as technology helps understand how the ice sheets respond to climate change.
One recent research project led by scientists from Dartmouth University suggests that temperature is the driving factor in shaping the size of Peru’s Quelccaya Ice Cap. The 17-square mile glacier in the Andes has been shrinking dramatically in the past few decades, making it a global warming symbol.
The findings support the idea that tropical glaciers are rapidly shrinking because of a warming climate — not because of a lack of snowfall. The study results will help scientists to better understand the natural variability of past and modern climate and to refine models that predict tropical glaciers’ response to future climate change. Continue reading
Filed under: climate and weather, Environment, global warming | Tagged: Andes, climate change, glaciers, global warming, Quelccaya Ice Cap | 2 Comments »
Posted on February 4, 2014 by Bob Berwyn
New data shows at least one glacier moving at a record pace of 50 feet per day
By Summit Voice
FRISCO — Arctic ice researchers say detailed measurements show that one Greenland’s glaciers has been moving at a record speed the past few years.
The scientists with the University of Washington and the German Space Agency measured the movement of the Jakobshavn Isbræ (Jakobshavn Glacier) in 2012 and 2013, concluding that the glacier is moving four times as fast as during the 1990s.
“We are now seeing summer speeds more than 4 times what they were in the 1990s on a glacier which at that time was believed to be one of the fastest, if not the fastest, glacier in Greenland,” said Ian Joughin, a researcher at the Polar Science Center, University of Washington and lead-author of the study. Continue reading
Filed under: climate and weather, Environment, global warming | Tagged: climate change impacts, glaciers, global warming, greenland, sea level rise | Leave a comment »
Posted on January 17, 2014 by Bob Berwyn
New study documents pace of ice loss in world’s tallest mountain
By Summit Voice
FRISCO — Melting Himalyan glaciers may not be causing a direct rise in sea level, but in some cases, the water is causing lakes overflow, flooding valuable agricultural land.
Glaciers are important indicators of climate change. Global warming causes mountain glaciers to melt, which, apart from the shrinking of the Greenlandic and Antarctic ice sheets, is regarded as one of the main causes of the present global sea-level rise.
Tibet’s glaciers have been losing mass at the rate of about 16 gigatons per year for the past decade. That loss is spread across about 80 percent of Tibet’s glaciers, according to Tobias Bolch, a glaciologist from the University of Zurich. That’s more than four times the volume of water in Lake Zurich and around six percent of the total loss in mass of all the glaciers on Earth. Continue reading
Filed under: climate and weather, global warming | Tagged: glaciers, global warming, Himalaya, sea lv | 1 Comment »