Global assessment of trends in wetting and drying over land
Global assessment of trends in wetting and drying over land
复制标题
DOI：
10.1038/ngeo2247
复制
发表时间：
2014-10-01
影响因子：
18.3
通讯作者：
Seneviratne, Sonia I.
中科院分区：
文献类型：
--
作者：
Greve, Peter;Orlowsky, Boris;Seneviratne, Sonia I.
地表水文条件的变化对社会产生重大影响(1,2)。然而，对观察到的大陆干旱趋势的评估得出了相互矛盾的结果(3-7)。随着气候变暖，干旱地区进一步干燥，而湿润地区变得更加湿润的概念已被提出，作为预期8-10以及观察到的(10-14)陆地变化的简化总结，尽管这个概念主要基于海洋数据(8,10)。在这里，我们对 1948 年至 2005 年期间历史土地干旱变化的各种水文数据集的 300 多个组合进行了分析。每个数据集组合都以蒸发、降水和干旱之间的经验关系为基准。那些表现良好的组合用于趋势分析。我们发现，全球约四分之三的陆地面积无法检测到剧烈的干旱变化。全球只有 10.8% 的陆地面积呈现出强烈的“干变得更干，湿变得更湿”的模式，而全球 9.5% 的陆地面积则呈现相反的模式，即干变得更湿，湿变得更干。我们的结论是，土地的干旱变化（直接社会经济后果的可能性最高）并未遵循现有模式的简单加剧。
Changes in the hydrological conditions of the land surface have substantial impacts on society(1,2). Yet assessments of observed continental dryness trends yield contradicting results(3-7). The concept that dry regions dry out further, whereas wet regions become wetter as the climate warms has been proposed as a simplified summary of expected8-10 as well as observed(10-14) changes over land, although this concept is mostly based on oceanic data(8,10). Here we present an analysis of more than 300 combinations of various hydrological data sets of historical land dryness changes covering the period from 1948 to 2005. Each combination of data sets is benchmarked against an empirical relationship between evaporation, precipitation and aridity. Those combinations that perform well are used for trend analysis. We find that over about three-quarters of the global land area, robust dryness changes cannot be detected. Only 10.8% of the global land area shows a robust 'dry gets drier, wet gets wetter' pattern, compared to 9.5% of global land area with the opposite pattern, that is, dry gets wetter, and wet gets drier. We conclude that aridity changes over land, where the potential for direct socio-economic consequences is highest, have not followed a simple intensification of existing patterns.