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Glaciers occupy more than 8,4 thousand km2, which is about 6 % of the total country area. The stock of snow and ice in all glaciers exceeds 500 km3. Glaciers form abundant water resources and influence local climate conditions.
The research of Tajikistan’s glaciers started in the end of 19th century. Since then, a “Catalogue of glaciers” was composed; the regions of ancient ice accretion were identified; glaciers dynamics and processes of glacier formation and melting were studied.
At present time there is an evidence of Tajikistan’s glaciers reduction, both in area and volume, which probably, can be explained by temperature rise and changes in precipitation.
In the second half of 20th century the Gissar-Alai glaciers in Central Tajikistan decreased by 1/3, and lost half of their former ice volume. Ice cover on the southern slopes of Gissar range is degrading. Small glaciers (1 km2) comprising the majority in this region are melting very intensively, which affects the river flow.
Small glaciers on the western slopes of Peter I range within Surkhob river basin melt intensively. On the Alai southern slopes, the ice cover is decreasing slower, since this is the area of bigger glaciers.
The degradation of glaciers occurs in the Pamirs. The biggest in the country Fedchenko glacier (length is about 70 km), located in the upper stream of Muksu river, during the 20th century retreated for almost 1 km; its area decreased to 11 km2, and it lost about 2 km2 of ice. Almost all of its right side tributaries separated from the main glacier body. However, the degradation of this ice giant is slower than other glaciers.
The biggest glacier Garmo, located in the Obihingou river basin melt intensively. During the 20-th century, this glacier shortened by almost 7 km, having lost more than 6 km2 of its area. At present this glacier retrieves on average by 9 meters a year; because of melting its surface caves 4 meters a year. Skogach glacier located in the same river basin retrieves yearly by 11 meters. In the Western Pamir, the glacier Bakchighir in the Gunt river basin retrieved 530 meters from 1960 to 1990; its surface caved 5 meters during that period; the glacier lost many millions of cubic meters of ice.
Climate warming is also observed in the Eastern Pamir. However, in view of high altitudes and severe climate, local glaciers retrieve slower than in other regions of the country. The glacier M. Octyabrski located at the altitude of 4500 meters above sea level retrieves on average 10 meters a year; the glacier Akbaital for 2-5 meters a year.
At a conservative estimate, Tajikistan’s glaciers in the 20th century lost more than 20 km of ice. Small glaciers, (1 km2) which constitute 80% of all glaciers and comprise 20% of the total ice cover melt intensively. The most intensive degradation is observed at the glaciers located on the southern slopes (Zeravshan, Garmo); the most stable are the glaciers with northern exposition (Fedchenko, Skogach).
Below is a tentative prediction of the glaciation dynamics over the territory of Tajikistan up to 2050-s. This prediction is based on the various climate change scenarios and data from the Institute of Geography of the Academy of Sciences of Russian Federation and Central Asian Hydrometeorological Research Institute (Uzbekistan).
During the next fifty years, hundreds of small glaciers in the Zeravshan river basin will melt. The bigger ones will lose 20-30% of their volumes. By 2050-s, the ice cover in Zeravshan basin will reduce by 20-25%, and the ice volume will decrease by 30-35%. As a result, the ice feeding will almost halve.
Glaciers on the southern slopes of Gissar range will halve (Central Tajikistan). Small glaciers in the Surkhob river basin will melt because of insufficient snowfall. Hundreds of small glaciers on the right-side slopes will disappear. The ice cover will reduce by 15-20%, and the ice volume will decrease by 25-30%. However some bigger glaciers will remain.
Fedchenko glacier in Muksu river basin will lose about 3-5% of its ice volume. At the same time, another glaciers in this basin will lose 15-20% of their ice volumes.
Obihingou river basin for the next fifty years may lose up to 25% of ice area, and 35% of ice volume. Apparently, Garmo glacier will significantly degrade. Small glaciers will totally disappear.
Western Pamir will lose many small glaciers. Generally, ice cover here will reduce by 15-20%, and ice volume by 20-25%. Eastern Pamir will face less significant degradation, in comparison with other regions because of high altitude.
Thus, thousands of small glaciers in Tajikistan will disappear by 2050-s. Countrywide, the ice cover will reduce by 20%, and the ice volume will decrease by 25%. Ice feeding of many rivers will decrease dramatically.
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