HR: 0800h
AN: GC41A-0090    [Abstracts]
TI: Space-Based Observations of Batura Glacier Fluctuations, Western Karakoram Himalaya
AU: * Shroder, J F
EM: jshroder@mail.unomaha.edu
AF: Department of Geography and Geology, University of Nebraska at Omaha, Omaha, NE 68182, United States
AU: Bishop, M P
EM: jshroder@mail.unomaha.edu
AF: Department of Geography and Geology, University of Nebraska at Omaha, Omaha, NE 68182, United States
AU: Haritashya, U K
EM: uharitashya@mail.unomaha.edu
AF: Department of Geography and Geology, University of Nebraska at Omaha, Omaha, NE 68182, United States
AU: Bulley, H N
EM: hbulley@mail.unomaha.edu
AF: Department of Geography and Geology, University of Nebraska at Omaha, Omaha, NE 68182, United States
AU: Olsenholler, J A
EM: jolsenholler@mail.unomaha.edu
AF: Department of Geography and Geology, University of Nebraska at Omaha, Omaha, NE 68182, United States
AU: Mertes, J R
EM: jmertes@mail.unomaha.edu
AF: Department of Geography and Geology, University of Nebraska at Omaha, Omaha, NE 68182, United States
AB: Monitoring glacier variations by our GLIMS (Global Land Ice Measurements from Space) Regional Center for Southwest Asia (Afghanistan and Pakistan) shows unusual fluctuations over a 40 year period for Batura Glacier. We use multiple field measurements (1984, 1991, 1992, 1993), maps and the work of others (1966, 1974, 1975, 1978, 1980), and satellite imagery (KH-9 Lower Resolution Mapping Camera 4/Aug/1973; Landsat MSS 15/Jul/1979; SPOT 20/Jun/1990; Landsat 5 TM 15/Oct/1992; Landsat 7 ETM 29/Oct/2000 & 30/Sep/2001; ASTER 29/Oct/2003 & 13/Sep/2004). The terminus was at the Hunza River in late 19th and first half of 20th century and then retreated rapidly ~800 m by 1966, leaving behind prominent end moraines on the north terminus. Declassified KH-9 imagery of 1973 shows Batura Glacier width, due south of Shanoz midway between the Chinese cross sections VI and VII, was only ~1523 m wide, whereas after Chinese mapping of 1974-75, and in all imagery thereafter, width there increased to >2 km. Batura does not surge and kinematic waves have not been detected. An ice cliff had formed at the terminus in 1966, advanced forward 100 m and thickened by 15 m by 1975, and advanced another 33 m by 1978, perhaps from this heretofore undetected, probable kinematic wave. Then instead of advancing as predicted by Chinese scientists, by 1984 the frontal ice cliff had retreated 50-100 m, declined in slope angle, and was covered with debris and vegetation, which makes the slope still visible on recent imagery. Our orthorectified imagery shows that from 1973 – 2004 the front of the white ice stream from the first ice fall on the right (south) side underwent retreat of ~2846 m, (retreat rate of 92m yr-1), mainly through down- wasting increase of debris cover and new melt-water lakes. Similarly the terminus underwent ~392 m of retreat from 1973 – 1990 (~23 m yr-1 annual retreat rate), ~36 m retreat from 1990-1992, (~18 m yr-1 annual retreat rate), and a ~37 m advance (~3 m yr-1 annual advance rate) from 1992-2004. High-resolution imagery on Google Earth™ acquired in 2005 or thereafter shows an exposed-ice terminus that has advanced ~50 m from 2004 on. A large new ice cliff has emerged on the southeast side ~ 275 m behind the present ice terminus, even while the parent south white-ice-stream source continued to retreat up-ice. The Chinese Batura Glacier Investigation Group used mass balance and tree-ring data in the 1970s to predict glacier advance from the 1970s, cessation in 1991 – 1997, and retreat for 20 – 30 years thereafter. Global cooling was hypothesized with advances again by 2060, but the actual situations have been otherwise.
DE: 0720 Glaciers
DE: 0758 Remote sensing
DE: 0762 Mass balance (1218, 1223)
DE: 0776 Glaciology (1621, 1827, 1863)
DE: 1621 Cryospheric change (0776)
SC: Global Environmental Change [GC]
MN: 2007 Fall Meeting