Heterogeneity analysis of main driving factors affecting potential evapotranspiration changes across different climate regions

Wenhui Liu; Baozhong Zhang; Zheng Wei; Yaqi Wang; Ling Tong; Jingyang Guo; Xin Han; Congying Han

doi:10.1016/j.scitotenv.2023.168991

Heterogeneity analysis of main driving factors affecting potential evapotranspiration changes across different climate regions

Sci Total Environ. 2024 Feb 20:912:168991. doi: 10.1016/j.scitotenv.2023.168991. Epub 2023 Dec 1.

Authors

Wenhui Liu¹, Baozhong Zhang², Zheng Wei³, Yaqi Wang³, Ling Tong⁴, Jingyang Guo³, Xin Han⁵, Congying Han³

Affiliations

¹ State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing 100038, China; College of Water Resources and Civil Engineering, China Agricultural University, Beijing 100083, China.
² State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing 100038, China. Electronic address: zhangbaozhong333@163.com.
³ State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing 100038, China.
⁴ College of Water Resources and Civil Engineering, China Agricultural University, Beijing 100083, China.
⁵ State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing 100038, China; College of Water Conservancy Engineering, Tianjin Agricultural University, Tianjin 300392, China.

PMID: 38043808
DOI: 10.1016/j.scitotenv.2023.168991

Abstract

Exploring the influencing factors of potential evapotranspiration (PET) is of great significance for further understanding the causes of climate change and improving agricultural irrigation efficiency. In this study, modified Mann-Kendall analysis was used to elucidate the temporal variation characteristics of meteorological factors and PET based on a dataset from 710 meteorological stations in China. Furthermore, we revealed the main factors that influence the temporal and climate heterogeneity of PET by combining sensitivity analysis with the contribution analysis method. The results showed that 1) climate factors and PET exhibited trend changes on a yearly scale, with slope variation ranges of temperature (T), relative humidity (RH), net radiation (RN), wind speed (U) and PET of 0.03-0.04 °C/a, 0.03-0.08 %/a, 0.001-0.007[MJ/(m²/day)]/a, -0.005 to -0.012(m/s)/a and -0.30-0.38 mm/a, respectively. 2) The sensitivity coefficient fluctuated greatly inter-annually, but the trend was more pronounced inter-annually. Most sensitive factor for PET was RN in hyperarid (HAR), arid (AR) and semiarid regions (SAR), while it changed to RH in semihumid (SHR) and humid regions (HR). PET was more sensitive to RN in dry and relatively wet hot seasons, while it changed to RH during wet and relatively dry cold seasons. 3) PET changes were determined by the relative changes and the sensitivity coefficient, and significant temporal heterogeneity was observed. In HAR, AR, SAR and SHR, the relative changes in T and U result in higher contributions. In HR, PET changes were primarily caused by its higher sensitivity to RH and RN. 4) In dry region and humid-cold seasons, the bigger relative changes of climate factors were the main drivers affecting PET changes, but in humid region and arid-hot seasons, the they were determined by the strong nonlinear relationship between PET and factors. This finding holds great significance for the scientific understanding of the evolution mechanism of PET under changing environments.

Keywords: Climate regions; Contribution amount; Multi-time scale; Potential evapotranspiration; Sensitivity coefficient.