Breckenridge Destinations supports independent journalism. Click for great deals on vacation lodging in Breckenridge.
The majestic Aletsch Glacier, the largest in the European Alps, will probably lose about about 50 percent of its volume in the next few decades. PHOTO FROM THE WIKIMEDIA COMMONS.
Smaller glaciers will melt faster and fuel sea level rise
By Summit Voice
SUMMIT COUNTY — A new study by Canadian researchers suggests that smaller glaciers in mountain regions will be especially hard-hit by global warming, with many of them likely to shrink by 50 percent from their current ice volumes.
The melt-off from those glaciers will contribute to about 12 centimeters of sea-level rise by 2100, according to the University of British Columbia research published this week in Nature Geoscience.
“There is a lot of focus on the large ice sheets but very few global scale studies quantifying how much melt to expect from these smaller glaciers that make up about 40 percent of the entire sea-level rise that we observe right now,” said Valentina Radic, a postdoctoral researcher with the university’s department of earth and ocean sciences and lead author of the study.
The study modelled volume loss and melt off from 120,000 mountain glaciers and ice caps, and is one of the first to provide detailed projections by region. Currently, melt from smaller mountain glaciers and ice caps is responsible for a disproportionally large portion of sea level increases, even though they contain less than one per cent of all water on Earth bound in glacier ice.
Increases in sea levels caused by the melting of the Greenland and Antarctic ice sheets, and the thermal expansion of water, are excluded from the results.
The largest contributors to projected global sea-level increases are glaciers in Arctic Canada, Alaska and landmass bound glaciers in the Antarctic. Glaciers in the European Alps, New Zealand, the Caucasus, Western Canada and the Western United Sates–though small absolute contributors to global sea-level increases–are projected to lose more than 50 per cent of their current ice volume.
Radic and colleague Regine Hock at the University of Alaska, Fairbanks, modelled future glacier melt based on temperature and precipitation projections from 10 global climate models used by the Intergovernmental Panel on Climate Change.
“While the overall sea level increase projections in our study are on par with IPCC studies, our results are more detailed and regionally resolved,” Radic said. “This allows us to get a better picture of projected regional ice volume change and potential impacts on local water supplies, and changes in glacier size distribution.”
Global projections of sea level rises from mountain glacier and ice cap melt from the IPCC range between seven and 17 centimeters by the end of 2100. Radic’s projections are only slightly higher, in the range of seven to 18 centimeters.
Radic’s projections don’t include glacier calving–the production of icebergs. Calving of tide-water glaciers may account for 30 per cent to 40 per cent of their total mass loss.
“Incorporating calving into the models of glacier mass changes on regional and global scale is still a challenge and a major task for future work,” says Radic.
However, the new projections include detailed projection of melt off from small glaciers surrounding the Greenland and Antarctic ice sheets, which have so far been excluded from, or only estimated in, global assessments.
Filed under: climate and weather, Colorado, Environment, global warming, Summit County Colorado Tagged: | Aletsch Glacier, Alps, Antarctic ice sheet, Environment, glaciers, global warming, Intergovernmental Panel on Climate Change, Nature Geoscience, sea level rise, Summit County Colorado, Summit County News, University of Alaska Fairbanks, University of British Columbia
Arapahoe Basin supports independent journalism. Click to visit The Legend online.
Powder's falling at Monarch!! Have you reserved your spot yet?
Innovative energy underwrites coverage of energy stories.
In fact, the NOAA has commissioned and launched satellites for the specific purpose of determining the global impact of ice sheet coverage. you can view part of it at http://www.natice.noaa.gov/ims/ .
It is interesting that news of advances in scientific knowledge is generated on data that can be determined by taking a large ice cube and a small ice cube and setting them on your kitchen counter and seeing how fast they melt per unit volume with a stopwatch. This article is bogus sensationalist media science at it’s worst. You can do far better in helping the public understand the phenomenon.
Point taken, Mark, but I still think this study is interesting in that it looked specifically at glaciers by region and tried to quantify sea level increase from the melting of “smaller” glaciers.
Thank you for your kind reply. I feel that it is more important to relate these phenomena to local issues such as increased river levels, effect on water supplies, erosion concerns, wildlife dependence, and agricultural effects. The global effect is going to occur whether we want it to or not. The focus has to be shifted to relevant action in local communities. Thank you again for letting me express these concerns. Agree or not, The Summit County Citizen’s Voice is an outstanding journal and important forum. Discussion is how we work together to find answers.