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Интеллектуальная Система Тематического Исследования НАукометрических данных |
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The glaciology of the Russian High Arctic from Landsat satellite imageryстатья
- Авторы: Dowdeswell J.A., Dowdeswell E.K., Williams M., Glazovskii A.F.
- Сборник: U.S. Geological Survey Professional Paper
- Серия: Satellite Image Atlas of Glaciers of the World. Part 1386-F: Asia
- Том: 1386
- Год издания: 2010
- Место издания: U.S. Government Publishing Office Washington, D.C
- Первая страница: 94
- Последняя страница: 125
- Аннотация: The Russian High Arctic archipelagos of Franz Josef Land (Zemlya Frantsa-Iosifa), Severnaya Zemlya, and Novaya Zemlya, fringing the Barents and Kara (Karaskoye) Seas, contain more than 56,000 km2 of glaciers and ice caps, or about 10 percent of the Earth’s ice outside Antarctica and Greenland. In the Russian Far East, ice covering an area of less than 100 km2 occurs in the DeLong archipelago (Ostrova De-Longa), east of the ice-free New Siberian Islands (Novosibirskiye Ostrova). Relatively little is known about the glaciology of some of these islands. However, Landsat satellite imagery has provided a valuable descriptive and interpretative tool for acquiring base¬line glaciological data, despite problems of cloud cover which restrict the number of high-quality images available. Drainage basins are a basic unit for glaciological measurements, and for modeling ice dynamics and responses to climate change. Ice divides throughout the Russian High Arctic have been mapped from Landsat imagery to define catchment basin geometry. Major ice-cap outlet glaciers have been identified from Landsat data, and sources and magnitudes of iceberg production have been investigated. The largest icebergs observed were more than 2 km long at the Znamenity Glacier (Lednik Znamenityy), located on Vilchek Land (Zemlya Vil’cheka) in the Franz Josef Land archipelago, and more than 4 km long off the Matusevich Ice Shelf (Lednik Matusevicha) in Severnaya Zemlya. Fringing ice shelves were also identified from Landsat imagery of Franz Josef Land. Relatively few surge-type glaciers are present in the Russian High Arctic, but looped medial moraines indicate that a number of ice-cap outlets in Novaya Zemlya, and possibly Severnaya Zemlya, are of surge-type. Summer Landsat imagery displays marked zones of different brightness which are interpreted to represent, with increasing altitude, bare ice, slush, and snow. Some low-elevation ice caps in Franz Josef Land in particular may be undergoing rapid decay, with little or no net accumulation even at their crests. This decay is probably related to the termination of the cold “Little Ice Age” in the Eurasian Arctic about 100 years ago, combined with recent warming.
- Добавил в систему: Глазовский Андрей Федорович