摘要
通过分析天山南坡科其卡尔巴契冰川区的气候变化特征及其对冰川消融变化过程的影响,研究了冰川对气候变化的响应机理及其对塔里木河水资源的影响规律.科其卡尔巴契冰川区夏季气温比较高,基本处于正温,日较差较小;气温直减率较小,平均值为0 60℃·(100m)-1,冰川冷效应不明显;对流性降水较多,降水量的75%发生在白天;冰川区局地环流———山谷风发育,海拔3900m以上冰川受西风环流影响显著;净辐射在7月和8月中上旬均较大,在8月下旬后净辐射开始逐渐减小,与冰川消融是一致的.7月初至7月下旬是消融较强的两个时段,冰川平均消融速率为38 66mm·d-1,到8月中旬消融速率略有降低,平均为34 79mm·d-1,至9月中旬降至28 83mm·d-1.
Under global warming and climatic shift to warm-wet in the west regions of Northwest China in the 1980s, it is interested to know the recent variation of glacier in the Tarim River drainage. For analyzing the variation characteristics of climate and the factors affecting ablation, the mass balance, ice movement, hydrology, meteorology and so on were studied on a typical glacier the Keqicar Glacier. It is very important to research the mechanics of the glacier responding to climate change and the impact upon the water resources of the Tarim River. On the Keqicar Glacier there is much high air temperature in summer, higher than 0 ℃ all day long basically, and low diurnal range, so the daily ablation on the glacier terminal is very large as compared with adjacent glaciers. The lapse rate of are temperature is low, about 0.60 ℃·(100m)^(-1), so cold effect of glacier is not obvious. Local circulation——mountain-valley wind develops on the glacier; Influence of westerly is evident above 4 250 m a. s. l. The convectional precipitation is much more, 75% of which occurs in daytime, because there is much more cumulonimbus and convectional airflow. Diurnal variation of relative humidity is obvious and increases with altitude. Net radiation is lager in July and the first/middle ten days of August, and then radiation begins to decrease from the last ten days of August, which coincides with the ablation of glacier. Ablation is very strong from July 1^(st) to July 26^(th), with a mean ablation rate of 38.66 mm·d^(-1), then the rate decreases a little to the middle ten days of August, about 34.79 mm·d^(-1), and finally the rate decreases rapidly to the middle ten days of September, about 28.83 mm·d^(-1).
出处
《冰川冻土》
CSCD
北大核心
2004年第5期545-550,共6页
Journal of Glaciology and Geocryology
基金
国家自然科学基金项目(90202013
40371026)
中国科学院知识创新工程重大项目(KZCX1 10 06)资助
关键词
科其卡尔巴契冰川
气温
局地环流
太阳辐射
冰川消融
Keqicar glacier
air temperature
local circulation
solar radiation
glacier ablation
