新疆额尔齐斯河流域气温日较差变化特征及影响因子分析

利用新疆额尔齐斯河流域5个国家气象地面基准站1961—2013年最低、最高气温及年平均气温、降水量、风速、日照时数、相对湿度等逐日资料,通过累计距平法、滑动平均、线性回归法,对该流域DTR变化特征及空间分布进行分析,以探讨该地区气温变化的规律。结果表明:额尔齐斯河流域各地年、年代DTR总体上呈减小趋势,除阿勒泰市以外,其余各地减小趋势显著;四季DTR变化趋势不太一致,总体上呈现减小趋势;年DTR极大值和极小值均呈减小趋势。年均最高、最低气温均呈升高趋势,最低气温的快速升高和最高气温的缓慢升高是额尔齐斯河流域DTR减小的直接原因。年均DTR与热力因子中的平均气温、动力因子中的平均风速呈正相关,与热力因子中的日照时数、水分因子中的降水量、动力因子中的相对湿度呈负相关,影响流域DTR的主要因子为平均气温、降水量、平均风速,关联性最强的是平均气温,其次是降水量。影响各地DTR的主要因子有所不同。

Variation Characteristics of Diurnal Temperature and Influence Factors of Irtysh River in Xinjiang

By using maximum temperature,minimum temperature and mean temperature,sunshine duration,evaporation,precipitation,relative humidity,and average wind speed of 5 weather stations in Irtysh river valley in Xinjiang from 1961 to 2013,the spatial and temporal trends of the temperature in this region were studied through taking the method of climate trending rate,5 years running mean tread and Inverse distance weighted interpolation method.The main results were as followed:Diurnal temperature range (DTR) generally showed a reducing trend at scales of the year and decade,and except Altay City,the reduction trends of the rest regions in Irtysh river valley were all significant.Variation trends of DTR in each season were inconsistent,but generally showed reducing trend.Maximum and minimum values of annual DTR assumed reducing trend.Annual maximum and minimum temperature assumed increasing trend.Rapid increasing of minimum temperature and slow rising of maximum temperature were the direct causes of DTR decreasing.The average annual DTR was positively correlated with average temperature and average wind speed,and negatively correlated with sunshine duration,precipitation and relative humidity.Main factors affected the valley DTR were the average temperature,precipitation and average wind speed,and the strongest correlation factor was the average temperature,followed by precipitation.Main influence factor affected DTR varied from each station.