水是生命的源泉，又是极其宝贵的资源。西部地区年均降雨量多在150毫米以下，在建设西部的过程中，借鉴国外经验，向空中取水，润泽久旱的辽阔大地，是值得关注的重要环节。人所共知，大气中携雨（水汽）云团是地球淡水循环中的重要组成部分，拥有的水量可占到淡水总量的0．04? Water is the source of life and an extremely valuable resource. The average annual rainfall in the western region is more than 150 millimeters. In the process of building the western region, drawing on the experience of other countries, drawing water into the air and moisturizing the arid and vast expanse of land are important links of note. It is well known that the cloud carrying water (vapor) in the atmosphere is an important part of the earth’s freshwater cycle, and the amount of water it holds can account for 0.04% of the total fresh water volume.