Change-Point Analysis of Precipitation and Drought Extremes in China over the Past 50 Years

Abstract

Increases in climate extremes and their impacts have attracted global attention recently. In this study, the change-point years of precipitation extremes (PEs) and drought extremes (DEs) were investigated by Moving t-Test at 500 stations across the six regions in China. The detailed temporal change processes of them were demonstrated by the cumulative deviation method based on the data from nine typical stations. The results showed that: 1) DEs were more significantly and widely increased than PEs, the stations with increasing trends of PEs and DEs accounted for greater than 52.6% and 61.6% of the total, respectively; 2) increasing trends of DEs were mainly distributed in the east of Hu Huanyong Line. In this area, the increasing change-point years of DEs often occurred in the early 1980s in the south of the Yangzi River, while occurred in the 1990s in the north of the Yangzi River; 3) increasing trends of PEs were mainly distributed in Qing-Tibet Platen, Northwest China, and the southeastern area of Hu Huanyong Line. In these areas, the increasing change-point years of PEs often occurred around 1990 in the southeast of Hu Huanyong Line, while often occurred in the early 1980s in Qing-Tibet Platen. The results indicated that the area in the southeast of Hu Huanyong Line was under the threats of both PEs and DEs, this may produce severe impacts on agriculture, environment, water resources management, human society, etc.

Changes of Extreme Agro-Climatic Droughts and Their Impacts on Grain Yields in Rain-Fed Agricultural Regions in China over the Past 50 Years

“…Therefore, the insufficient total annual precipitation led to the Meanwhile, the distribution of the stations where the changepoint of increasing intensity in EAD occurred after 1984 was similar to that of stations with EAD frequency variation occurring after 1984. This analysis indicated that the number and distribution range of the stations with increasing EADs were less than those of the stations with increasing EDs [65]. However, the stations with increasing EADs and increasing EDs shared a similar change trend spatially.…”

“…Stations where the changepoint of increasing intensity in EAD occurred before 1984 were mainly distributed in Guangzhou, Guangxi, and Yunnan provinces (significant change-points), partial areas of Gansu and Ningxia provinces (significant change-points), and Shandong Province (insignificant change-point).Meanwhile, the distribution of the stations where the changepoint of increasing intensity in EAD occurred after 1984 was similar to that of stations with EAD frequency variation occurring after 1984. This analysis indicated that the number and distribution range of the stations with increasing EADs were less than those of the stations with increasing EDs[65]. However, the stations with increasing EADs and increasing EDs shared a similar change trend spatially.…”

Identifying the shift in global wildfire weather conditions over the past four decades: an analysis based on change-points and long-term trends

“…The nonstationarity in hydrometeorological variables, such as precipitation (Dhakal et al 2015;Gu et al 2019;Vu and Mishra, 2019), temperature (Aziz et al 2020;Carney et al 2020;Kärner, 2002), and drought index (Das et al 2020;Kwon and Lall, 2016;Wu et al 2020), has been extensively studied. Most of the existing research has focused on the long-term trends of hydrometeorological variables (Byakatonda et al 2018;Meshram et al 2017;Salman et al 2017) and on the change-points in these variables (Ahmadi et al 2018;Jiang et al 2019;Liu et al 2020). Such studies have discovered that, under the increasing influence of global warming, more high temperature events and extreme droughts have shown increasing trends of occurrence in the United States (Ge et al 2016), China (Ye et al 2019), Southeast Asia (Dong et al 2021), Australia (Sharples et al 2021), and Brazil (Geirinhas et al 2021).…”

Understanding the Role of Physiological and Agronomical Traits during Drought Recovery as a Determinant of Differential Drought Stress Tolerance in Barley

“…Climate trends and the current global warming have increased the frequency of drought events in the world by about threefold in the last 50 years [1]. As a result, the amount of land area affected by drought may reach 50% by the end of the century, and the frequency of extreme agricultural droughts events is projected to increase by about sixfold, with major drought events occurring every 5 years [2].…”