黄河上游阿尼玛卿山区冰川波动与气候变化

Glacier Fluctuations and the Inferred Climate Changes in the A′Nyêmaqên Mountains in the Source Area of the Yellow River,

以黄河上游阿尼玛卿山的冰川为研究对象 ,通过应用航空相片、卫星遥感影像、地形图和数字高程模型 (DEM) ,分析了末次冰盛期、小冰期、自 1 966年及 2 0 0 0年的冰川范围及变化情况 .结果表明 ,末次冰盛期的冰川范围是现代冰川的 3 .1倍 ;小冰期以来 ,冰川已经开始退缩 ,尤其在 1 966—2 0 0 0年期间退缩有加速趋势 .介绍了一种提取冰川雪线高度的方法 ,并根据现代气候数据 ,探讨了研究时段雪线高度上的夏季平均气温变化趋势 .结果表明 ,末次冰盛期时 ,雪线下降了 42 0m左右 ,相应的夏季平均气温比现代低 1 .9℃ ,小冰期盛时夏季平均气温比现代低 0 .6℃ .

The paper analyzes glacier variations during the Last Glacial Maximum (LGM), the Little Ice Age (LIA) maximum, and the period between 1966 and 2000 by applying aerial photos, satellite images, topographical maps and a derived digital elevation model (DEM) in the A'nyêmaqên Mountains in the source area of the Yellow River. The results indicate that glaciers in the LGM covered 3.1 times of the present glacier area in this region. Glaciers have shrunk since the LIA maximum and the decrease in area accelerated in the period between 1966 and 2000. A method has been used for extracting the glacier equilibrium-line altitude (ELA). Based on current climatic data, mean summer air temperatures at the ELA are reconstructed for some periods, indicating that mean summer temperature dropped by 2.1 ℃ in LGM, which corresponded to an ELA decrease of about 420 m with respect to that in 2000. There was a colder summer in the LIA maximum, when mean summer temperature was 0.6 ℃ lower than that of the present.