Thresholds for triggering the propagation of meteorological drought to hydrological drought in water-limited regions of China

Qiang Liu; Yuting Yang; Liqiao Liang; He Jun; Denghua Yan; Xuan Wang; Chunhui Li; Tao Sun

doi:10.1016/j.scitotenv.2023.162771

Thresholds for triggering the propagation of meteorological drought to hydrological drought in water-limited regions of China

Sci Total Environ. 2023 Jun 10:876:162771. doi: 10.1016/j.scitotenv.2023.162771. Epub 2023 Mar 11.

Authors

Qiang Liu¹, Yuting Yang², Liqiao Liang³, He Jun⁴, Denghua Yan⁵, Xuan Wang⁶, Chunhui Li⁶, Tao Sun⁶

Affiliations

¹ State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, China; Key Laboratory for Water and Sediment Sciences, Ministry of Education, School of Environment, Beijing Normal University, Beijing 100875, China. Electronic address: qiang.liu@bnu.edu.cn.
² State Key Laboratory of Hydroscience and Engineering, Department of Hydraulic Engineering, Tsinghua University, Beijing, China.
³ State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources (TPESER), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China. Electronic address: liangliqiao@itpcas.ac.cn.
⁴ General Institute of Water Conservancy and Hydropower Planning and Design, Ministry of Water Resources, Beijing, China.
⁵ State Key Laboratory of Simulation and Regulation of the Water Cycle in River Basins, China Institute of Water Resources and Hydropower Research, Beijing 100038, China.
⁶ State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, China; Key Laboratory for Water and Sediment Sciences, Ministry of Education, School of Environment, Beijing Normal University, Beijing 100875, China.

PMID: 36907388
DOI: 10.1016/j.scitotenv.2023.162771

Abstract

Propagation thresholds that trigger a transition between meteorological drought and hydrological drought are poorly understood, which hinders effective establishment of drought warning systems and prevention measures. Here, propagation thresholds were assessed by firstly identifying drought events during 1961-2016 in the Yellow River Basin, China, subsequently pooling, excluding, and matching them, and finally assessing their threshold conditions by using a combined Copula function and transition rate (T_r) analysis. These results show that response time changed according to variations in drought duration and watershed characteristics. Importantly, response times increased according to the timescales over which they were studied; for example, the Wenjiachuan watershed recorded response times of 8, 10, 10, and 13 months when examined at 1-, 3-, 6-, and 12-month timescales, respectively. Additionally, the severity and duration of meteorological and hydrological drought events both increased when events were combined rather than studied individually. These effects were also amplified for matched meteorological and hydrological droughts by factors of 1.67 (severity) and 1.45 (duration), respectively. Shorter response times were identified in the Linjiacun (LJC) and Zhangjiashan (ZJS) watersheds, and correlated with their relatively small T_r values of 43 % and 47 %, respectively. Higher propagation thresholds for drought characteristics (e.g., 1.81 and 1.95 for drought severity in the LJC and ZJS watersheds, respectively) imply that shorter response times tended to have greater effects on hydrological drought events and lowered their T_r, and vice versa. These results provide new insight into propagation thresholds used for water resource planning and management, and may help to mitigate the effects of future climate change.

Keywords: Copula; Drought propagation; Hydrological drought; Meteorological drought; The Loess Plateau.