Globally Increasing Atmospheric Aridity Over the 21st Century
Globally Increasing Atmospheric Aridity Over the 21st Century
复制标题
21世纪全球大气干旱度不断增加
DOI：
10.1029/2022ef003019
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发表时间：
2022-10-01
期刊：
影响因子：
8.2
通讯作者：
Fensholt, Rasmus
中科院分区：
文献类型：
--
作者：
Fang, Zhongxiang;Zhang, Wenmin;Fensholt, Rasmus
蒸气压赤字（VPD）对于控制水和二氧化碳的陆地-大气交换非常重要。在这里，我们使用现场观察来评估每月 VPD 的性能，该月度 VPD 是根据最先进的数据集（包括 CRU、ERA5 和现代时代研究与应用回顾分析，版本 2 (MERRA2)）计算得出的。我们根据耦合模型相互比较项目第 6 阶段 (CMIP6) 的输出调查了 1981-2020 年全球范围内和不同气候带的 VPD 趋势以及未来趋势 (2021-2100)。结果表明，CRU、ERA5 和 MERRA2 估计的月度 VPD 与 15,531 个世界气象组织站点的现场估计值具有良好的相关性，R-2 范围在 0.92 到 0.96 之间。此外，在现场站之间以及单独分析不同月份时也发现了强大的相关性。 1981-2020年，各气候区VPD均有所增加，其中干旱区增幅最强，其次是热带、温带、寒带和极地。 CMIP6模拟显示VPD（0.028 hPa a年（-1））呈持续增加趋势，其中干旱区增加幅度最大（0.063 hPa a年（-1））。我们发现，在未来排放情景中，随着二氧化碳排放量的增加，趋势的幅度也会增加。我们强调，在全球变暖的背景下，大气干旱化将持续下去，这可能对陆地生态系统，特别是旱地农业系统构成越来越大的威胁。
Vapor pressure deficit (VPD) is of great importance to control the land-atmosphere exchange of water and CO2. Here we use in situ observations to assess the performance of monthly VPD calculated from state-of-the-art data sets including CRU, ERA5, and Modern-Era Retrospective analysis for Research and Applications, Version 2 (MERRA2). We investigate trends in VPD at global scale and for different climatic zones for 1981-2020 and future trends (2021-2100) from Coupled Model Inter-comparison Project phase 6 (CMIP6) outputs. The results show that monthly VPD estimated from CRU, ERA5, and MERRA2 correlated well against in situ estimates from 15,531 World Meteorological Organization stations, with R-2 ranging between 0.92 and 0.96. Moreover, robust correlations were also found across in situ stations and when analyzing different months separately. During 1981-2020, VPD increased in all climatic zones, with the strongest increase in the arid zone, followed by tropical, temperate, cold and polar zones. CMIP6 simulations show a continuously increasing trend in VPD (0.028 hPa year(-1)), with the largest increase in the arid zone (0.063 hPa year(-1)). The magnitudes of trends are found to increase following the magnitude of CO2 increases in the future emission scenarios. We highlight that atmospheric aridification will continue under global warming, which may pose an increasing threat to terrestrial ecosystems and particularly dryland agricultural systems.