Tag Archives: glaciers

Latest report confirms rapid glacier melting

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The united States Geological Survey in its report published in collaboration with 39 international scientists says that glacier throughout the Asia region – Russia, China, Nepal, India, Bhutan, Pakistan, Afghanistan, Georgia, Kyrgyzstan, Tajikistan and Kazakhstan are retreating.

However the report says the time period for the retreat is different among the glaciers. “In Bhutan, 66 glaciers have decreased by 8.1 percent over the last 30 years. Rapid changes in the himalaya has been seen in India where Chhota Shigri Glacier has retreated by 12 per cent over the last 13 years and Gangotri Glacier – that is considered to have originated in 1780 witnessed 12 per cent shrinkage in the main stem in the last 16 years,” adds the report.

The melting of the glaciers in the himalayas ran into controversy after the intergovernmental panel on Climate change -  a scientific body under the United Nations Framework Convention on climate change to look into the issues of climate change -  apologized for the mistake in its fourth assessment report in 2007 that stated ‘the Himalayan glaciers will disappear by 2035 due to the impact of climate change’. himalayan glaciers

“This retreat impacts water supplies to millions of people, increases likelihood of outburst floods that threaten life and property in nearby areas and contributes to sea level rise,” states the USGS report.

As glaciers become smaller, water runoff decreases which is especially important during the dry season when other water sources are limited. Climate change also increases temperature and earlier water runoff from glaciers and this combined with spring and summer rains can result in flood conditions.

“The overall glacier retreat and additional melt can increase the amount of water in the vicinity of a glacier and the added pressure enhances likelihood of disastrous flooding,” warns the report. Tracing the history of glacier studies the report has mentioned that glacier studies in each area started at different times depending on accessibility of the glaciers and scientific interest. According to USGS, the earliest description of glaciers in China has been traced back to 630 AD, while studies in the Caucasus area of Russia began in the mid 1800s and modern studies in Nepal started in the 1950s.

“Glaciers in the Himalayas are a major source of fresh water and they feed water to all of the rivers in northern India. Of particular interest is the Himalaya where glacier behaviour impacts the quality of life of tens of millions of people,” said USGS scientist Jane Ferrigno.

Global sea level may rise by 12cm by 2100

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Melt-off from small mountain glaciers and ice caps will raise global sea levels 12 cm by 2100. The largest contributors to the projected sea level rise would be glaciers in Arctic Canada, Alaska and landmass-bound glaciers in the Antarctic, according to a new study.

Glaciers in the European Alps, New Zealand, the Caucasus, western Canada and the western US are projected to lose more than 50 per cent of their current ice volume, reported the journal Nature Geo science. The study modeled volume loss and melt-off from 120,000 mountain glaciers and ice caps and was one of the first to provide detailed projections by region, according to a University of British Columbia, Canada, statement. Currently, melt-off from smaller mountain glaciers and ice caps are responsible for a disproportionately large portion of sea level increases, even though they contain less than one percent of all water on Earth-bound glacier ice.

“There is a lot of focus on the large ice sheets but very few global scale studies quantifying how much melt-off to expect from these smaller glaciers that make up about 40 per cent of the entire sea level rise that we observe right now,” said Valentina Radic. Radic is a postdoctoral re-
searcher with the department of earth and ocean sciences of the university who led the study.

Increases in sea levels caused by the melting of the Greenland and Antarctic ice sheets, and the thermal expansion of water, were excluded from the results.  Radic and colleague Regine Hock at the University of Alaska, Fairbanks, modeled future glacier melt off based on temperature and precipitation projections from 10 global climate models used by the Intergovernmental Panel on Climate Change (IPCC).

“While the overall sea level increase projections in our study are on par with IPCC studies, our results are more detailed and regionally resolved,” said Radic.