黑河流域张掖市近38 a以来气候变化特征分析

 目前黑河流域气候变化研究多集中于流域系统气候变化与区域水资源变化之间的关系、区域沙漠化、沙尘暴发生的气候动因等研究方面，而对人类活动强度大、活动最为密集的流域绿洲区域张掖市气候变化所作研究较少。通过对张掖市六县（区）6个气象观测站近38 a以来的逐月平均气温、降水、大风频率资料的系统分析，认为张掖市近38 a来气温升高幅度较之全国其他区域更为明显。多年降水变化相对不大，但冬春两季降水出现缓慢增加的趋势，大风天气与沙尘暴发生频数近38 a来出现了明显的下降趋势，这与区域气温升高及冬春两季易发生沙尘暴的期间降水增加有明显的相关性。同时人类对干旱区内陆河流域绿洲开发的加深也一定程度上对这种生态环境敏感地区的气候产生影响。

Climate Changing Characteristics of Zhangye City in Heihe River Basin During 1968-2005

At present,researches on climate changes of Heihe river basin mainly focus on the relationship between basin climate changes and regional water resources,regional desertification and dynamic climatic reasons of sand-dust storms,but less on climate change of oasis region,where human activities are the most dense and great intense.Based on data of precipitation,temperature,gale and sand-dust frequencies obtained from the six meteorological stations of Zhangye region in Heihe river basin,the features of climate changes were studied for 1969-2005. Results showed that the regional temperature increasing extension exceeded the average level of China;the annual precipitation changed a little,but the precipitation had slowly increase trend in spring and winter;the frequencies of gale and sand-dust storm days showed obviously descending trends,which had close correlation to the regional temperature increase and the precipitation increase in spring and winter.Meanwhile,the further human economic activities and exploitations to the oasis in inland valley of arid region also effected the climate change in this sensitively fragile eco-environment region.