摘要
基于1992、2002、2008年三个时相TM数字遥感影像和1:10万地形图数据,通过目视解译方法提取冰川面积,研究了青藏高原腹地长江源头各拉丹东地区冰川变化问题。结果表明:各拉丹东地区总冰川面积自1992年以来呈持续下降趋势,面积由1992年的931.59km2减少至2002年的927.66km2,至2008年时缩减至915.13km2。1992~2008年冰川面积共减少了16.46km2,年平均递减约1.03km2,总面积减少约1.77%。2002-2008年总面积下降约1.35%,约为1969-2000年的31a间冰川消融面积的80%,表明近二十年青藏高原腹地冰川退缩速率明显加快。进一步分析发现,面积较小的冰川其消融或退缩速度更快,面积较大的则相对较为缓慢。在总体退缩趋势下,2号冰川末端部分地区2002年出现了增长趋势,其变化趋势表现为:退缩-短暂前进-退缩。对影响冰川变化气候因子分析表明,近几十年青藏高原地区升温所引起的气候变暖是影响20世纪90年代中期以来该地区冰川加速消融的根本原因,气候显著变暖冰川明显退缩。
Dynamic change of Geladandong glaciers in area of headwaters of the Yangtze River in the hinterland of Qinghai-Tibetan Plateau were analyzed by using the 1992,2002,2008 Landsat satellite TM image and 1:100,000 topographic map and the method of man-machine visual conversation discriminated glaciers area manually.It was found that the total area of glaciers showed a distinctly decreasing trend since 1992.Glacier area was 931.59km2,927.66km2,and 915.13km2in 1992,2002 and 2008 respectively.Reduced area was about 1.77% from 1992 to 2008 and about 1.35% during 2002 ~ 2008 which was approximately 80% area that decreased from 1969 to 2000.It indicated the decrease rate of glacier area was significant greater than previous period in the hinterland of Qinghai-Tibetan Plateau.Furthermore,the results showed a greater melting pace in smaller glacier area than larger area.The pattern of some glaciers variation can be summarized as follows: " Withdrawal-short-term advance-retreat".The glacier variation respond to temperature and precipitation showed a strong corresponding in this area,it is implied that climate warming dominated a quickly decreases of glacier area since mid-1990s.
出处
《干旱区资源与环境》
CSSCI
CSCD
北大核心
2014年第3期142-147,共6页
Journal of Arid Land Resources and Environment
基金
国家自然科学基金项目(41173085
41061002)
高原气象开放基金(LPM20090005)资助
关键词
冰川
各拉丹东
青藏高原
遥感
气候变化
glacier
Geladandong
Qinghai-Tibet Plateau
remote sensing
climate change