全球水循环放大效应被高估 2016年12月9日,英国南安普顿大学在《科学报告》( Scientific Reports )上发表了一篇题为“全球水循环放大速度小于克劳修斯—克拉珀龙方程率”( Global water cycle amplifying at less than the Clausius-Clapeyron rate )的文章。文章称:地球上潮湿的区域将会变得越来越潮湿,而干旱地区将会越来越缺水,但是这种现象的发展速度比我们之前想象的要慢很多。 研究主要是基于对全球海洋盐分含量进行的科学分析。某一特定区域内,更多的降雨量以及因降雨量增多导致该区域流向海洋的河水增多,会使海洋盐分含量被稀释,因此海水的咸度降低。而在其他地区,因干旱气候的蒸发作用,使得这些干旱地区的淡水被蒸发掉之后仅仅留下其中的盐分,因此这就导致干旱环境变得“更咸”。 研究人员对全球以及海洋深处的盐含量进行测定,用这种方式来评估过去60年期间全球降雨量的变化方式。他们发现,在那些相对较湿的地区,如欧洲北部,在过去60年当中,潮湿地区变得越发潮湿,其总体湿度比60年以前提高了2%,同样干旱地区的干燥程度也增加了2%。这种过程即为水文循环的放大效应(amplification of the water cycle)。之前有相关研究结果表明每当全球温度上升1℃,水文循环的放大效应就会以7%的速率影响环境湿度的变化。这项新的研究再次对这种放大效应进行了更全面的评估,计算得到的结果为全球气温每上升1℃,放大效应以3%~4%的速度发挥作用。研究团队认为水文循环放大效果的降低主要是由于大气环流作用(将干旱地带的淡水转移至潮湿地带)导致。 南安普敦大学的研究员Nikolaos Skliris表示,他们的发现结果与全球气候变暖模式的预测结果相一致,即:当全球气温不断上升时,潮湿地区会越加潮湿,而干旱地区会持续干旱。“尽管我们已经发现这个正在进行的过程比我们预期的速度放慢很多,但是如果全球气温再升高3℃,全球潮湿地区的湿度变化速率将达到10%,同样干旱地区也会以相同速率持续干旱下去。这会为全球河流与农业发展带来灾难性后果。” Skliris博士还强调,气候变化模式与他们对过去几十年观察结果的一致性是这次研究的另一个重要组成部分,因为这个结果再一次证明了在全球温室气体排放的影响下气候变化模式项目对水文循环放大效应的可信程度。 来源:《气候变化动态》 发布时间:2017年01月18日15:47
水循环过程中,除了自然力驱动的水的自然水循环,还包括社会力所驱动的社会水循环。在社会水循环过程中,内在驱动力是水的经济社会效益,而外在的物化表现则是电力驱动的水泵。 Vast amounts of energy are needed for the transportation, distribution and treatment of water. Pumping it over mountain ranges or from deep underground aquifers also requires a significant amount of energy. But the largest share of energy use comes from individual customers who heat water to bathe, cook and run businesses. 研究结果正如上面所说, 能源消耗最大的位于用水终端的个体水消费者。 Results: (1)In the sector of water extraction and delivery, only 23% of electricity requirements are used for water pumping out, purification, and distribution. Energy costs varydepending on the pumping distance, water quality, water pipelines, and water source. Groundwater pumping can increase energy use 30% over surface water sources. (2) End use: In this sector, up to 73% electricity requirements are needed in water cycle by homes, farms, and businesses. It is reported that household appliance such as washing machine, dishwasher, water heaters, and dryers use the largest amount of electricity in water cycle, 28%. (3) Waste water management just costs only 4% energy, which not only reveals waste treatment currently need less energy but shows there is lot of potentiality we can clean much moredischargedwater again. So far, only 4% electricity was used for water cleaning before it is discharged to water source. However, with the population growth and increasingly stringent treatment standards, more and more energy is needed, which could soon lead to increased wastewater management costs. Discussion Based on the results above, I suggest we should shift our eyes from water to energy and water together. How to do some comprehensive research on water cycle driven by energy requirements should be the focus of water cycle research in the future.