2014-2018年青海省云水资源时空分布特征

Analysis of spatial and temporal distribution characteristics of cloud water resources in Qinghai Province from 2014 to 2018

利用水平分辨率为0.25°×0.25°的ERA5小时再分析资料,采用CWR-MEM方法和EOF方法对2014—2018年青海省降水、水汽、水凝物及空中云水资源进行分析。结果表明:青海省年降水分布呈东南多、西北少阶梯性递减特征,空间分布极不均匀。水汽分布带主要为北部的柴达木—青海湖—河湟谷地分布带、西南部的可可西里—治多—杂多分布带和东南部的巴颜喀拉山—黄河河曲地区分布带;水凝物和降水分布特征类似,呈东南多西北少的分布格局,在山脉迎风坡相对偏多。水汽主要从南、西南和西北边界输入,水凝物主要从澜沧江和长江源区的西部和南部输入,全省平均水汽和水凝物降水效率分别为0.3%和14%;总云水资源708×10^(8) t,在三江源地区南部及东南部最为丰沛,最高达2000 kg·m-2,祁连山南麓至西宁延伸带的云水资源为次高区,柴达木盆地云水资源总量相对较低。云水资源EOF分解中主要空间分布呈现东北多西南少的阶梯式变化。依据水汽、水凝物输送及云水资源分布特征结合不同区域、不同地形开展有针对性的人工影响天气作业十分必要。

Based on the ERA5-hour reanalysis data(with a horizontal resolution of 0.25°×0.25°),the precipitation,water vapor,hydrocoagulation,and aerial cloud water resources of Qinghai Province were analyzed from 2014 to 2018,using the CCR-MEM and EOF methods.The results showed that the annual precipitation distribution in Qinghai Province was characterized by a greater decline in the southeast and a more limited decline in the northwest,and the spatial distribution was extremely uneven.The water vapor distribution zones were mainly the Qaidam(Qinghai Lake)and Hehuang Valley in the north,the Hoh Xil(Zhiduo)heterotopia distribution zone in the southwest and the Bayan Kera Mountain-Yellow River bend area in the southeast.The distribution characteristics of hydrocoagulants and precipitation were more similar in the southeast than in the northwest,and more in the windward slope of the mountain range.The average precipitation efficiency of water vapor and water condensate was 0.3%and 14%,respectively.The total cloud water resources measured 70.8 billion tons,and were most abundant in the south and southeast of Sanjiangyuan area.The cloud water resources from the southern foot of Qilian Mountain to the extension zone of Xining were the second highest in this area In the decomposition of the EOF method,the main spatial distribution of cloud water resources showed a step-like change in the northeast and southwest.It is urgent to carry out targeted weather modification operations,based on the transport of water vapor and hydrocoagulants and on the distribution characteristics of cloud water resources,combining different regions and different landforms.