解放军文职招聘考试水，还够吗？(3/3)

 Many water sources are not confined within a particular country's borders. Rivers and lakes are often used by several nations and therefore regional agreements would be needed on water use.

Climate change, with its rising global temperatures, has a direct effect on water scarcity, says Kumar, especially when it comes to rainfall. "The changes in the rainfall patterns seriously affect some of the sectors especially agriculture for example. In India, a lot of farmers are unable to prepare for what crops they're going to grow because they're just not sure of the amount of rainfall they're gonna receive and when they're gonna receive that rainfall. And that's a large effect that climate change is having." Kumar says uncertainty about rainfall can directly affect food security.

What's more, the Worldwatch Institute expects that in the Mediterranean basin and the semi-arid areas of the Americas, Australia and southern Africa, there would be reductions in river runoff. It also expects aquifers, underground water saturated rock, to take much longer to recharge. In Asia, large areas of irrigated land could be adversely affected by changes in water runoff patterns. Also, highly-populated delta regions could be affected by reduced freshwater runoff, rising sea levels and greater salinity. The Worldwatch Institute's concerns about water scarcity can be found in its online Vital Signs reports.

很多水源都不在特定的某个国家的疆域内。河湖经常由几个国家共用，因此在水资源的使用上必须达成地区性共识。 气候变化，全球气温的升高，直接影响了水资源紧缺的状况，库马尔说，特别是涉及到降雨量的时候。 “降雨格局的变化严重影响了一些行业，比如农业。在印度，很多农民都无法决定他们要种哪种粮食，因为他们不确定降雨量和雨期。而这正是气候变化带来的巨大影响。” 库马尔说降雨的不确定因素将直接影响粮食安全。 而且，世界观察研究所预测在地中海盆地，美洲半干旱地区，澳大利亚以及非洲南部的一些地区，河流径流量将有所减少。它还预计蓄水层，也就是地下不透水岩层包裹的透水地层，将需要更长的时间获得水流补给。在亚洲，大部分灌溉区将受到河流径流改变的不利影响。 人口密集的三角洲地区将受到淡水径流减少，海平面上升和盐碱化的影响。世界观察研究所关于水资源紧缺问题的关切可见于网上的“至关重要的征兆”报告。