Geologists have found a zone of anomalous growth of glaciers in the Himalayas

MOSCOW, April 15 — RIA Novosti. French geologists discovered the abnormal area of ice cover in the Great Himalayas, where local glaciers gradually gaining weight, and not decrease, as do the rest of ice massifs in the mountains and across the globe, according to a paper published in the journal Nature Geoscience.

It is believed that climate change is largely manifested today in the reduction of glaciers in the polar regions and at high altitudes in other areas of the Earth. In February 2012, the U.S. climate scientists estimated the total loss of the global ice cover by GRACE satellites and found that its melting every year, "adds" about 1.5 mm to global sea level. However, they found that the Himalayan glaciers have decreased much less than predicted by the model.

Group of geologists led by Julie Gardel (Julie Gardelle) from the University of Grenoble (France) confirmed the unusual nature of the Himalayan glaciers by comparing the three-dimensional maps of elevations, describing the state of glaciers in 2000 and 2008.

Gardel and her colleagues examined data from the U.S. space shuttle "Endeavour" in 2000 as part of SRTM mapping and geodetic satellite SPOT5 in 2008. Geologists have used them to produce three-dimensional profiles of the glacier, suitable for comparison.

To compare models geologists have calculated the height of several flat areas of the surface in the open and stable terrain outside the glaciers in the two models and the difference in height between them. This allowed the researchers to "impose" three-dimensional maps to each other and compare them. In addition, scientists have minimized the influence of other factors not related to the change of the area and the thickness of the ice surface — fluctuations in the thickness of the seasonal snow cover and some other items.

It turned out that in the Karakoram Mountains — the northwestern part of the Great Himalayas — is quite a large area of the area of 5.6 thousand square kilometers, where the ice cover is not only not changed, but a slight increase in eight years.

According to calculations of Gardel and her colleagues, the Karakoram glaciers added approximately 11-33 centimeters per year or remained virtually unchanged for the most conservative estimates. Accordingly, the overall contribution of the glaciers in the global sea level rise is minus 0.006 millimeters per year. In other words, the growth of the Karakoram glaciers reduces the level of the sea, rather than increasing it.

On the other hand, the glaciers in other parts of the Himalayas continue to fall: they lose about 310 pounds of ice per square meter of ice per year, which corresponds to an annual reduction in the thickness of glaciers by about 70 centimeters.

The authors plan to continue the study of the region to uncover the reasons why the western glaciers remain in thickness and are knocked out of the world trend, whereas the eastern follow them.

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