近50年来天山地区典型冰川厚度及储量变化

冰川储量变化与冰川水资源量变化以及冰川对河川径流的贡献量密切相关.在GPR-3S技术支持下,本研究基于雷达测厚数据、不同时期的高分辨率遥感影像、地形图及实测资料,分析了天山三个典型地区四条代表性冰川近期厚度及储量变化特征,并通过对比探讨了造成变化差异的可能原因.结果表明,1962-2006年乌鲁木齐河源1号冰川厚度平均减薄0.15m a-1,冰储量亏损26.2×106 m3,冰川末端平均退缩3.8 m a-1；博格达峰南坡的黑沟8号冰川在1986-2009年间,冰舌平均减薄0.57ma-1,冰储量损失了25.5×106m3,末端平均退缩11.0 ma1；位于博格达峰北坡的四工河4号冰川在1962-2009年间冰舌平均减薄0.32 m a-1,冰储量亏损14.0× 106 m3,末端平均后退8.0m a-1；1964-2008年间,托木尔峰青冰滩72号冰川冰舌平均减薄0.22 m a-1,由此至少造成冰储量亏损14.1×106 m3,末端退缩达40.0 m a-1.对比分析显示,青冰滩72号冰川消融退缩最为强烈,黑沟8号冰川次之,与乌鲁木齐河源1号冰川、科其喀尔冰川相差不大,稍大于四工河4号冰川和哈密庙尔沟冰川.这种差异可能与区域气候变化和冰川物理特征有直接关系.

Changes of Ice-thickness and Volume for Representative Glaciers in Tianshan Mountains in the Past 50 Years

Changes of glacier volume is directly related to glacial water resources and contribution of glacier changes to river runoff. With the support of GPR-3S technology, this paper studied ice-thickness and volume changes of the four typical glaciers in the three areas of Tianshan Mountains in recent years based on radar survey data, high-resolution remote sensing image, topographic maps and observation data. Furthermore, a comparison was made between the changes of these glaciers and the possible causes for the differences were analyzed. Results indicated that Urumqi Glacier No.1 underwent thinning of 0.15 m a -1 with the ice-volume loss of 26.2 × 10 6 m 3 and retreated by 3.8 m a -1 during 1962-2006. During 1986-2009, the ice tongue of Heigou Glacier No.8 on the south slope of Mt. Bogda thinned by 0.57 m a -1 , corresponding to the loss in ice-volume of 25.5×10 6 m 3 . At the same time, the terminus retreated by 11.0 m a -1 . The ice-thickness of Glacier No.4 of Sigong River located on the north slope of Mt. Bogda decreased to 0.32 m a -1 with an ice-volume loss of 14.0×10 6 m 3 over the period 1962-2009. The glacier terminus retreated by 11.0 m a -1 in the same period. For Qingbingtan Glacier No.72 in the Tomor region, the ice tongue thinned by 0.22 m a -1 , corresponding to a loss of ice-volume of 14.1 × 10 6 m 3 during 1964-2008. The glacier terminus retreated by 40.0 m a -1 in the same period. Results indicated that Qingbingtan Glacier No.72 retreated most intensively, followed by Heigou Glacier No.8, which differed slightly from Urumqi Glacier No.1 and Keqikaer Glacier. However, its changing magnitude was slightly larger than that of Glacier No.4 of Sigong River and Hami Miaoergou Glacier, indicating that such differences were directly influenced by regional climate change and physical features of glaciers.