title: Does drought in China show a significant decreasing trend from 1961 to 2009?
abstract: In recent decades, the occurrence and severity of drought in China has had devastating impact on social and economic development. The increase in drought has been attributed to global warming. We used the high-accuracy self-calibrating Palmer Drought Severity Index (scPDSI) to investigate the variation in drought in China between 1961 and 2009 using the Mann-Kendall (MK), continuous wavelet transform (CWT) and the rotated empirical orthogonal function (REOF) methods. We also analyzed the relationship between the rotated principal component time series (RPCs) and 74 circulation indices. The results revealed that: 1) all of China experienced a significant wet trend at annual and seasonal scale; an abrupt change in the drought pattern occurred around 1970 with a 2-8-year significant period; 2) eight major sub-climate regions were identified: Northwest China, Northeast-Inner Mongolia Plateau, Greater Khingan Range area, Northern Tibetan Plateau, Southern Tibetan Plateau, Central China, Huang-Huai-Hai Plain and Southeast China. Of these regions, the Southern Tibetan Plateau experienced a significant wet trend, but the Northeast-Inner Mongolia Plateau and Northern Tibetan Plateau became significantly drier. Using either annual or seasonal scales, Northwest China became significantly wetter and Central China became more arid. In addition, the period of each sub-climate region shared a significant 2-8-year band; 3) the polar vortex exhibited dominant patterns that affected most areas of China. The Pacific Decadal Oscillation had a significant influence on drought evolution, especially for Northwest China and the Huang-Huai-Hai plain. Additionally, the El Niño-Southern Oscillation also affected drought evolution, and the Central China was impacted by the Indian Ocean Dipole.
authors.affiliation: School of Civil Engineering and Transportation, South China University of Technology, Guangzhou 510641, China; POWERCHINA Huadong Engineering Corporation Limited, Hangzhou 310014, China.
authors.forename: Zhaoli
authors.initials: Z
authors.lastname: Wang
authors.affiliation: School of Civil Engineering and Transportation, South China University of Technology, Guangzhou 510641, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Li
authors.affiliation: School of Civil Engineering and Transportation, South China University of Technology, Guangzhou 510641, China; Center for Water Resource and Environment, Sun Yat-Sen University, Guangzhou 510275, China. Electronic address: laichg@scut.edu.cn.
authors.forename: Chengguang
authors.initials: C
authors.lastname: Lai
authors.affiliation: School of Civil Engineering and Transportation, South China University of Technology, Guangzhou 510641, China.
authors.forename: Zhaoyang
authors.initials: Z
authors.lastname: Zeng
authors.affiliation: School of Civil Engineering and Transportation, South China University of Technology, Guangzhou 510641, China.
authors.forename: Ruida
authors.initials: R
authors.lastname: Zhong
authors.affiliation: Center for Water Resource and Environment, Sun Yat-Sen University, Guangzhou 510275, China; Guangdong Engineering Technology Research Center of Water Security Regulation and Control for Southern China, Guangzhou 510275, China.
authors.forename: Xiaohong
authors.initials: X
authors.lastname: Chen
authors.affiliation: School of Civil Engineering and Transportation, South China University of Technology, Guangzhou 510641, China.
authors.forename: Xiaowen
authors.initials: X
authors.lastname: Zhou
authors.affiliation: POWERCHINA Huadong Engineering Corporation Limited, Hangzhou 310014, China.
authors.forename: Mingyuan
authors.initials: M
authors.lastname: Wang
keywords: China; Drought; Spatiotemporal characteristic; Sub-climate region; scPDSI_PM