作 者: (巩宁刚); (孙美平); (闫露霞); (宫鹏); (马兴刚); (牟建新);
机构地区: 西北师范大学地理与环境科学学院,甘肃兰州730070
出 处: 《干旱区地理》 2017年第4期762-771,共10页
摘 要: 采用1979-2016年ECMWF1.5o×1.5o逐月再分析资料及同期37个气象站点的降水资料,利用一元线性回归、累积距平、Kriging及IDW(反距离加权)等方法分析了祁连山地区大气水汽含量时空分布特征、降水转化率空间变化规律以及风场分布规律,并对比分析了中国西部不同地区降水转化率的变化趋势。结果表明:(1)1979-2016年祁连山地区大气水汽含量整体呈增加趋势,且季节变化明显。其中夏季是各层大气水汽含量最多的季节,高达329.24 mm,占多年平均大气水汽含量的48.1%。(2)近38 a来,祁连山地区的大气水汽含量呈东南多、西北少的空间分布,且随海拔的升高而逐渐减少,整层大气水汽主要集中在5 000 m以下。(3)祁连山地区的降水转化率从空间上表现出由东向西递减的趋势,说明该地区空中云水资源的开发潜力自东向西逐渐增强,空中云水资源的开发潜力区域差异明显;季风所携带的水汽对其影响区域的降水贡献率较高,西风所携带的水汽则对其影响区域的降水贡献率较低。(4)中国西部地区降水转化率呈向心式递减的趋势,且区域空间波动较大。 Qilian Mountains region is one of the most important water vapor cycle sites in arid and semi-arid areas of Northwest China,and the most important water vapor regulation area in Hexi Corridor.Based on the monthly reanalysis data of ECMWF 1.5°× 1.5° during 1979-2016 and precipitation data of 37 meteorological stations in corresponding period,by adopting approaches of monadic linear regression method,accumulative anomaly,Kriging and IDW,the paper analyzed the spatial-temporal characteristics of atmospheric water vapor content,the spatial changing rule of precipitation conversion rate and the distribution law of wind field in Qilian Mountains,and the change trend of precipitation conversion rate in westem China.Results show as follows:(1) The atmospheric water vapor showed an increasing trend in Qilian Mountains and the seasonal variation of atmospheric water vapor content showed a significant increase trend during 1979-2016.Summer had the most atmospheric water vapor in all layers,which was up to 329.24 mm,accounting for more than 48.1% of the annual average atmospheric water vapor content.(2) In recent 38 years,the atmospheric water vapor content in the Qilian Mountains region decreased from southeast to northwest;meanwhile,the water vapor content decreased gradually with the rising of altitude.Atmospheric water vapor of the whole layer mainly concentrated below 5 000 m,and from 875 hPa (about 1 253 m) to 550 hPa (about 5 000 m),the water vapor content accounted for 92.2% of the total water vapor content.(3) The precipitation conversion rate showed a decrease trend from the east to west in Qilian Mountains,with an average rate of 36.2%,a maximum rate of 76.2%,and a minimum rate of 3.8%,indicating that the development potential of the space cloud water resource enhanced gradually from east to west,the regional difference of developing potential of cloud water resource was obvious.The water vapor carried by the monsoon had a high contribution to the precipitation in the region,whil