Long-term Change of Seasonal Snowcover and Its Effects on Runoff Volume in the Upper Reaches of the Tarim River
Long-term Change of Seasonal Snowcover and Its Effects on Runoff Volume in the Upper Reaches of the Tarim River
复制标题
DOI：
--
复制
发表时间：
2005
期刊：
影响因子：
--
通讯作者：
CM Cai-xia
中科院分区：
文献类型：
--
作者：
CM Cai-xia
汇入塔里木河的3条主要源流发源于山区，主要靠降水补给。山区地表径流量和地下水储量与季节性积雪的积累和融化密切相关。本文利用塔里木河上游17个气象站和源流区6个气象站1960~2003年44年的积雪≥0cm日数、最大季节积雪深度、夏季降水量和平均气温资料，以及1957 ~ 2000年2个水文站的观测资料，分析了塔里木河上游季节积雪的变化。并将季节性积雪变化与塔里木河主要源流之一阿克苏河径流量的长期变化趋势进行了比较。结果表明：自20世纪60年代以来，塔里木河上游季节积雪深度略有增加，但年际变化显著；与此相对应，阿克苏河径流量显著增加，特别是1993年以来，径流量平均增加13.475 m~3·s~（-1）·10a~（-1）。通过对上游夏季径流量与最大季节积雪深度、平均气温、降水的回归分析，认为径流量主要受夏季降水的影响，其次是季节性积雪深度和夏季最高气温的影响。因此，20世纪90年代以来塔里木河上游气候变暖是维持塔里木河源流径流量稳定的重要因素之一，说明气象因子在塔里木河流域地表径流形成过程中起着重要作用。积雪深度EOF分析结果表明，在气候变化背景下，塔里木河上游季节积雪空间分布较为稳定。
The 3 main source streams converging into the Tarim River rise in the mountainous regions and are recharged mainly by precipitation. Surface runoff volume and groundwater reserves are closely related to the accumulation and melt of seasonal snowcover in the mountainous regions. In this paper, the change of seasonal snowcover in the upper reaches of the Tarim River is analyzed using the data of the days with snowcover≥0cm, maximum seasonal snowcover depth and precipitation and average air temperature in summer, observed by 17 meteorological stations in the upper reaches of the Tarim River and 6 meteorological stations in the source stream areas during the 44-year period of 1960～2003 as well as 2 hydrological stations during the period of 1957—2000, and the change of seasonal snowcover is compared with the long-term change trend of runoff volume of the Aksu River, one of the main source streams of the Tarim River. The results show that the seasonal snowcover depth in the upper reaches of the Tarim River has slightly increased since the 1960s, but its annual change is significant. Correspondingly, the runoff volume of the Aksu River has been significantly increased, especially since 1993, and the average increase rate is 13.475 m~3·s~(-1)·10a~(-1). After carrying out the regression analysis between the runoff volume and the maximum seasonal snowcover depth and average air temperature and precipitation in summer in the upper reaches, it is considered that the runoff volume is mainly affected by precipitation in summer, then the seasonal snowcover depth and the maximum air temperature in summer. Therefore, the climatic warming-wetting in the upper reaches of the Tarim River since the 1990s is one of the very important factors for maintaining the stable runoff volumes of the source streams of the Tarim River, which reveals that the meteorological factors play an important role in the formation of surface runoff in the Tarim River watershed. The analyzed results of EOF of snowcover depth reveal that the spatial distribution of seasonal snowcover in the upper reaches of the Tarim River is quite stable under the background of climate change.