Solved the mystery of resistant Karakoram glaciers

A unique weather pattern, which preserves the cold and dry ice in summer, keeps the Karakoram glaciers safe from the regression that these ice streams suffer worldwide.

This is the conclusion of a study published in Nature Geoscience to seek explanation for the 'Karakorum anomaly', by which the glaciers of this mountain range west of the Himalayas have not lost volume over time.

    "It has been a source of controversy that these glaciers have not changed while other glaciers in the world do have them," said Sarah Kapnick, postdoctoral researcher in Atmospheric Sciences and Ocean at Princeton University, and lead author of the study .

    The new climate model Princeton team has 17 times more detailed used by the Intergovernmental Panel on Climate Change (IPCC) (2,500 square kilometers off 44,100 square kilometers) resolution.

    The new model simulates changes in temperature and precipitation change in three major regions of the Himalaya (Karakoram, Himalayas central and southeastern Himalayan plateau) from 1861 to 2100. The IPCC global climate models overestimate the temperature in the region because they could not conform to the topographic variations of the area of Karakorum. As a result, models have underestimated the amount of snow that falls on the glacier. The new climate model successfully simulates the seasonal cycles of temperature and precipitation.

MORE SNOW DURING THE MONSOON

    Unlike the rest of the Himalayas, the Karakoram is not adversely affected by the summer monsoon season, as has been found Kapnick. The precipitation that occurs during the summer in the rest of the Himalaya never reaches the regions of Karakorum until winter, when the temperature is already cold.

    The temperature in the area is then averaged below freezing, contributing to excess snow received in the winter when the western winds bring precipitation to the mountains of Afghanistan.

    This advantage of westerly winds will not last long, however. If climate change continues its current trend, including the Karakoram be affected. Kapnick considers that this climatic advantage can reach 2100. After that is unclear.

    Understanding the patterns of snowfall in the Himalayas can contribute to a better understanding of regional climate change. Moreover, the results of this research can make a difference in water management processes at regional level. The glaciers of the Himalayas are the main water reserve for hundreds of millions of people in India, Pakistan and China.

Bu Haber için yorum yapabilirsiniz 24.02.2015 14:15:33 207.241.237.227

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