On the coupling between precipitation and potential evapotranspiration: contributions to decadal drought anomalies in the Southwest China

  • Author(s): Sun, Shanlei; Chen, Haishan; Ju, Weimin; Wang, Guojie; Sun, Ge; Huang, Jin; Ma, Hedi; Gao, Chujie; Hua, Wenjian; Yan, Guixia
  • Date: 2016
  • Source: Climate Dynamics
  • Station ID: JRNL-SRS-2016

Abstract

Under the exacerbation of climate change, cli· mate extreme events. especially for drought, happened frequently and intensively across the globe with greater spatial differences. We used the Standardized Precipitation-Evapotranspiration Index computed from the routine meteorological observations at 269 sites in Southwest China (SWC) to study the drought characteristics (e.g., extent, duration and intensity) and their decadal variations during I 971 - 2012. It was revealed that the drought, in responses to the coupling between decadal precipitation and potential evapotranspiration (PET) nnomalies, differed among regions and periods. For the entire SWC, droughts in 1970s and 2000s+ was generally stronger than in 1980s and 1990s with respect to their spatial extent, duration and intensity, especially in 2000s+. It was well -known that drought was closely related with a Jack of precipitation; however, the impact of atmospheric demand of evaporation (reflected by PET here) on drought (e.g., duration and intensity) was rarely paid enough attentions. To that end, a spatial multi-linear regression approach was proposed in this study for quantifying the contributions of decadal PET and precipitation variations to drought duration and intensity. We have found that the contributions of decadal PET anomalies to drought duration and intensity could exceed those of precipitation, e.g., during 1980s and 1990s in SWC. Additionally. despite the strongest droughts in 2000s+, it was suggested that PET could exert comparable impacts on drought anomalies as precipitation. All these findings implied that PET plays a critical role in drought event, which acts to amplify drought duration and intensity. To sum up, this study stressed the need for enough attentions for PET processes in drought studies.

  • Citation: . . On the coupling between precipitation and potential evapotranspiration: contributions to decadal drought anomalies in the Southwest China. Climate Dynamics. doi: 10.1007/s00382-016-3302-5

Requesting Publications

You can order print copies of our publications through our publication ordering system. Make a note of the publication you wish to request, and visit our Publication Order Site.

Publication Notes

  • This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.
  • Our on-line publications are scanned and captured using Adobe Acrobat. During the capture process some typographical errors may occur. Please contact the SRS webmaster if you notice any errors which make this publication unuseable.
  • To view this article, download the latest version of Adobe Acrobat Reader.