期刊名称:ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences
印刷版ISSN:2194-9042
电子版ISSN:2194-9050
出版年度:1992
卷号:XXIX Part B7
页码:87-94
出版社:Copernicus Publications
摘要:in light of the recent, apparent global warming trend. Despitethe fact that the Southern Patagonia Icefield (SPI) is the largestice body of temperate glaciers in the southern hemisphere, therecent variation of its outlet glaciers has not been systematicallystudied. Utilizing Landsat MSS (1976) and TM (1986) digitaldata, digitized aerial photographs taken in the late 1960s and1970s, trimetrogon aerial photographs taken in 1944/45, andmaps produced from them, we elucidated variations of six majoroutlet glaciers, Bni'ggen, Jorge MonU, O'Higgins, Upsala,Moreno and Tyndall glaciers distributed in the SPI, from 1945to 1986. While most glaciers showed a general recession, upto more than 13 km in the 41 year period, Bruggen glacieradvanced about 9 km between 1945 and 1976, and blocked afjord, with the result of the snout splitting into the northern andsouthern tongues. The southern tongue of Briiggen Glacier hadslightly retreated, however, between 1976 and 1986, while thenorthern tongue had continued to advance. Breaking the 41 yearperiod into two by the intermediate date of the late 1960s or1970s, we found for the recent 10-15 years an acceleratedrecession at Upsala Glacier, slow downs at O'Higgins andTyndall glaciers, and a relatively steady rate at Jorge MonttGlacier. On the Landsat mosaic of the SPI, the icefield area wasmeasured and found to have diminished by about 500 km2 toaround 13,000 km2 in 41 years. The surface lowering has beenalso considerable, more than 100 m, at some glaciers. As awhole, the SPI has been loosing a considerable amount of icesince 1945.
关键词:Southern Patagonia Icefield; Recent Glacier;Variation; Landsat TM and MSS Digital Data