Temporal and spatial evolution of the standardized precipitation evapotranspiration index (SPEI) in the Loess Plateau under climate change from 2001 to 2050

Xuerui Gao; Qi Zhao; Xining Zhao; Pute Wu; Wenxiang Pan; Xiaodong Gao; Miao Sun

doi:10.1016/j.scitotenv.2017.03.226

Temporal and spatial evolution of the standardized precipitation evapotranspiration index (SPEI) in the Loess Plateau under climate change from 2001 to 2050

Sci Total Environ. 2017 Oct 1:595:191-200. doi: 10.1016/j.scitotenv.2017.03.226. Epub 2017 Apr 4.

Authors

Xuerui Gao¹, Qi Zhao², Xining Zhao³, Pute Wu⁴, Wenxiang Pan⁵, Xiaodong Gao⁶, Miao Sun⁷

Affiliations

¹ Institute of Soil and Water Conservation of Northwest A&F University, No. 26 Xinong Road, Yangling, 712100, Shaanxi, China.. Electronic address: gaoxuerui666@163.com.
² College of water Resources and Architectural Engineering, Northwest A&F University, No. 3 Taicheng Road, Yangling 712100, Shaanxi, China. Electronic address: zhaoqi20@126.com.
³ Institute of Soil and Water Conservation of Northwest A&F University, No. 26 Xinong Road, Yangling, 712100, Shaanxi, China.. Electronic address: xiningz@aliyun.com.
⁴ Institute of Soil and Water Conservation of Northwest A&F University, No. 26 Xinong Road, Yangling, 712100, Shaanxi, China.. Electronic address: gjzwpt@vip.sina.com.
⁵ College of water Resources and Architectural Engineering, Northwest A&F University, No. 3 Taicheng Road, Yangling 712100, Shaanxi, China. Electronic address: panwx1992@126.com.
⁶ Institute of Soil and Water Conservation of Northwest A&F University, No. 26 Xinong Road, Yangling, 712100, Shaanxi, China.. Electronic address: donniao@gmail.com.
⁷ College of water Resources and Architectural Engineering, Northwest A&F University, No. 3 Taicheng Road, Yangling 712100, Shaanxi, China. Electronic address: 313709190@qq.com.

PMID: 28384575
DOI: 10.1016/j.scitotenv.2017.03.226

Abstract

Loess Plateau has great uncertainty on drought occurrence due to climate change. This paper analyzes the evolution of precipitation, potential evapotranspiration and standardized precipitation evapotranspiration index (SPEI) based on the Coupled Model Inter-comparison Project Phase 5 (CMIP5) data and regional downscaling model (RegCM4.0). Results indicate that, under RCP2.6 Scenario, the precipitation will increase significantly (5% confidence level) at the rate of 16.40mm/10a. However, the potential evapotranspiration is showing non-significant decreasing trend at the rate of 2.16mm/10a. Moreover, the SPEI will decrease in the south and northernmost area and increase in the central northern area of Loess Plateau. Under RCP8.5 Scenario, the precipitation will increase significantly (5% confidence level) at the rate of 19.12mm/10a. The potential evapotranspiration will non-significantly decrease at the rate of 2.16mm/10a and the SPEI is showing increasing trend almost in the whole Loess Plateau. Generally, Loess Plateau is becoming wetter in the central part under RCP2.6 Scenario and the wet area will be enlarged to almost the whole plateau under RCP8.5 Scenario. Based on the results, the water resources will increase under global warming, which may alleviate the water scarcity issue in the Loess Plateau.

Keywords: Climate change; Drought; Loess Plateau; Potential evapotranspiration; Precipitation; SPEI.