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JOURNAL OF GEOPHYSICAL RESEARCH,
VOL. 110,
D16101,
doi:10.1029/2004JD005642,
2005
Spatial and temporal variability in active layer thickness over the Russian Arctic drainage basin
Tingjun Zhang
National Snow and Ice Data Center, Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder,
Colorado, USA
Oliver W. Frauenfeld
National Snow and Ice Data Center, Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder,
Colorado, USA
Mark C. Serreze
National Snow and Ice Data Center, Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder,
Colorado, USA
Andrew Etringer
National Snow and Ice Data Center, Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder,
Colorado, USA
Christoph Oelke
Institute for Geophysics, University of Münster, Münster, Germany
James McCreight
National Snow and Ice Data Center, Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder,
Colorado, USA
Roger G. Barry
National Snow and Ice Data Center, Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder,
Colorado, USA
David Gilichinsky
Institute for Physiochemical and Biological Problems in Soil Science, Russian Academy of Sciences, Pushchino, Moscow Region,
Russia
Daqing Yang
Water and Environmental Research Center, University of Alaska, Fairbanks, Alaska, USA
Hengchun Ye
Department of Geography and Urban Analysis, California State University, Los Angeles, California, USA
Feng Ling
Department of Computer Science and Technology, Zhaoqing University, Zhaoqing, Guangdong Province, China
Svetlana Chudinova
Institute for Physiochemical and Biological Problems in Soil Science, Russian Academy of Sciences, Pushchino, Moscow Region,
Russia
Abstract
Changes in active layer thickness (ALT) over northern high-latitude permafrost regions have important impacts on the surface
energy balance, hydrologic cycle, carbon exchange between the atmosphere and the land surface, plant growth, and ecosystems
as a whole. This study examines the 20th century variations of ALT for the Ob, Yenisey, and Lena River basins. ALT is estimated
from historical soil temperature measurements from 17 stations (1956–1990, Lena basin only), an annual thawing index based
on both surface air temperature data (1901–2002) and numerical modeling (1980–2002). The latter two provide spatial fields.
Based on the thawing index, the long-term average (1961–1990) ALT is about 1.87 m in the Ob, 1.67 in the Yenisey, and 1.69
m in the Lena basin. Over the past several decades, ALT over the three basins shows positive trends, but with different magnitudes.
Based on the 17 stations, ALT increased about 0.32 m between 1956 and 1990 in the Lena. To the extent that results based on
the soil temperatures represent ground “truth,” ALT obtained from both the thawing index and numerical modeling is underestimated.
It is widely believed that ALT will increase with global warming. However, this hypothesis needs further refinement since
ALT responds primarily to summer air temperature while observed warming has occurred mainly in winter and spring. It is also
shown that ALT exhibits complex and inconsistent responses to variations in snow cover.
Received 30
November
2004;
accepted 1
June
2005;
published 18
August
2005.
Keywords: permafrost;
active layer;
Russian Arctic.
Index Terms: 1823 Hydrology: Frozen ground; 1824 Hydrology: Geomorphology: general (1625); 1834 Hydrology: Human impacts; 1863 Hydrology: Snow and ice (0736, 0738, 0776, 1827).
Read Full Article (file size: 1956104 bytes) Cited by
Citation: Zhang, T., et al.
(2005),
Spatial and temporal variability in active layer thickness over the Russian Arctic drainage basin,
J. Geophys. Res.,
110,
D16101,
doi:10.1029/2004JD005642.
Copyright 2005 by the American Geophysical Union.
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