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Peculiarities of modern changes of the total and underground runoff in North-East Russia |
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| © 2018 V. E. Glotov, L. P. Glotova |
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| North-East Interdisciplinary Scientific Research Institute n. a. N. A. Shilo FEB RAS, Magadan |
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| E-mail: ;
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| The north-east of Russia, with its area of about 1.5 million km2, is hydrologically the largest peninsula divided into the Arctic and the Pacific slopes by the Great Divide of the Earth. It is established that the features of the current changes in water flow in the Arctic and northern areas of the Pacific slope are manifested in the fact that the current warming of the climate causes a decrease in the overall flow of rivers with an increase in the share of underground feeding in the winter low water. In the southern Pacific slope and in the Sea of Okhotsk basin, the effect of climatic warming is an increase in total runoff, including its subsurface constituents. We associate these peculiarities of river runoff with the cryolithic zone environments. Over the Arctic slope and the northern Pacific slope, where the cryolithic zone is continuous, the subsurface constituent of the total runoff results from discharge of ground waters hosted in seasonally thawing rocks. Warmer climatic conditions favor vegetation growth, which requires more water for evapotranspiration and evaporation from rocky surfaces in the summertime. In the Sea of Okhotsk basin, where the cryolithic zone is discontinuous, not only ground waters in seasonally thawing layers, but also continuous taliks and subpermafrost waters participate in processes of river recharges. Therefore, greater biological productivity of the vegetation cover shows no effect on the ground-water supply and river recharge processes With a steady climate warming, a continuous cryolithic zone can presumably degrade into a discontinuous, and then into an island-type permafrost layer. In such case, there will be a general increase in the total runoff and its subsurface constituent. In terms of geoecology, a greater runoff is is positive, while its possible minor negative consequences can be prevented.> |
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| Keywords: North-East of Russia, Great Divide of the Earth, climatic warming, cryogenic aquicludes, total runoff, subsurface recharge. |
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