Glacier meltwater and runoff modelling, Keqicar Baqi glacier,southwestern Tien Shan, China
Glacier meltwater and runoff modelling, Keqicar Baqi glacier,southwestern Tien Shan, China
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DOI：
10.3189/172756507781833956
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发表时间：
2007
影响因子：
3.4
通讯作者：
Yong Zhang;Shi-yin Liu;Yongjian Ding
中科院分区：
文献类型：
--
作者：
Yong Zhang;Shi-yin Liu;Yongjian Ding
摘要利用修正的度日模式，结合线性水库模式，模拟了2003年7月1日至9月12日天山西南部的大型冰川克其卡尔巴其冰川的融水和径流。有很好的协议之间的模拟和测量消融桩的融水和模拟和观测到的冰川末端径流。重建冰川融水和径流从一个假设的碎片的表面在研究期间表明，冰川融水产生的碎片层的影响至关重要地影响冰川径流。该模型还被用来计算冰川径流量的气候情景造成的二氧化碳加倍的ReCM2区域气候模型预测。预计温度和降水量的变化分别为0至2.7°C和0至25%。结果表明，冰川径流量随温度线性增加，在这些范围内是否考虑碎片层。温度变化的影响比降水量变化的影响显著得多。由于碎片层主要覆盖（和绝缘）的消融区域，冰川径流的响应是不太敏感的温度增加与碎片覆盖的表面比与碎片自由表面。在+2.7°C情景中，当冰川面积减少时，冰川径流也会显著减少。
Abstract Meltwater and runoff from Keqicar Baqi glacier, a large glacier in the southwestern Tien Shan, northwestern China, are simulated using a modified degree-day model including potential clear- sky direct solar radiation, coupled with a linear reservoir model for the period 1 July to 12 September 2003. There is good agreement between modelled and measured meltwater at ablation stakes and between simulated and observed runoff at the glacier terminus. A reconstruction of glacier meltwater and runoff from an assumed debris-free surface during the study period shows that the effect of the debris layer on glacier meltwater generation crucially affects glacier runoff. The model is also used to calculate glacier runoff given the climate scenario resulting from a doubling of CO2 as projected by the ReCM2 regional climate model. The projected changes in temperature and precipitation vary from 0 to 2.7°C and from 0 to 25%, respectively. Results indicate that glacier runoff increases linearly with temperature over these ranges whether or not the debris layer is taken into consideration. The effect of change in temperature is much more noticeable than that for change in precipitation. Due to the debris layer predominantly covering (and insulating) the ablation area, the response of glacier runoff is less sensitive to temperature increase with a debris-covered surface than with a debris-free surface. Glacier runoff is also markedly reduced when a reduced glacier area is prescribed in the +2.7°C scenario.