HR: 1340h
AN: GC23A-0983    [Abstracts]
TI: The Whole Tien Shan Glacier Area Changes Between 1973 and 2003 Estimated From Corona and ASTER Satellite Imagery
AU: * Surazakov, A B
EM: asurazakov@vandals.uidaho.edu
AF: Department of Geography, University of Idaho, McClure 203, Moscow, Id 83844-3021, United States
AU: Aizen, V B
EM: aizen@uidaho.edu
AF: Department of Geography, University of Idaho, McClure 203, Moscow, Id 83844-3021, United States
AU: Aizen, E M
EM: eaizen@uidaho.edu
AF: Department of Geography, University of Idaho, McClure 203, Moscow, Id 83844-3021, United States
AB: Changes in glacier covered area of the Tien Shan Mountains (western, central and eastern) was estimated between 1973-2003 using Corona KH-9 (9 m) and ASTER (15 m) imagery. Large spatial coverage of a single Corona KH-9 photograph (almost eight ASTER images) and accurate geometric qualities of the KH-9 frame- mapping camera provide a unique opportunity for reconstruction of the glacier covered area during the last 30 years with comparable spatial resolution. The images were orthorectified using SRTM DEM with void areas filled with ASTER DEM and ground control points collected from 1:25,000 and 1:50,000 topographic maps. The Corona and ASTER orthorectification RMS residuals were in the same order of 7-15 m. Glacier boundaries were derived using segmentation of ASTER 3N/4 band ratio and manual digitizing with error-checking in stereo viewing. Since the middle of 1970s, Tien Shan was experiencing abrupt increase in air temperature, that accelerated glacier recession particularly in the mountain ranges lower than 5,000 m a.s.l. From 1973 to 2003 all Tien Shan glaciers have significant recession trend. The most notable recession has been observed in the western and southern Tien Shan: from 20% to 17.1% of the total glacier area. The eastern and northern Tien Shan glaciers have lost 12.6% - 11% of their total area while the largest and highest (up to 7,000 m) central Tien Shan remained nearly the same glacierized area: only 1% of the total glacier area reduction. The large dendritic glaciers in the central Tien Shan are heavily covered by moraine debris, which protect glaciers from intensive ablation. The Tien Shan mountain ranges longitudinally spans more than 2,000 km and glaciers exist in different geo-morphological and climatic conditions determining the difference in glacier recession. However, the Tien Shan glacier surface has decreased in all regions and has to be measured by GPS and satellite altimetry to estimate real changes in glacier ice water resources.
DE: 0720 Glaciers
DE: 0758 Remote sensing
DE: 1621 Cryospheric change (0776)
DE: 1857 Reservoirs (surface)
DE: 9320 Asia
SC: Global Environmental Change [GC]
MN: 2007 Fall Meeting