Climate change impact on extreme value and its frequency distribution function in a karst basin, Southwest China

Chongxun Mo,Zhenxiang Xing,Xuan Song,Yuli Ruan,Guikai Sun,Xingbi Lei,Huakun Lan

doi:10.2166/wcc.2022.415

Abstract

Abstract Studying extreme meteorology and its frequency under climate change is helpful to guide flood and drought control. The original achievements and objective of this study are to further contribute to the literature on how to analyze the impact of climate change on extreme rainfall and extreme temperature more reasonably and comprehensively for a karst basin. The Mann–Kendall method, Heuristic segmentation method, cross-wavelet analysis method, generalized extreme value (GEV) model, and generalized Pareto distribution (GPD) model were applied in this paper. The 55-year (1963–2017) extreme rainfall and temperature data recorded in the Chengbi River Basin were applied. The results show that extreme rainfall showed a downward trend (−0.169 and −8.735 mm/10a), while the trends of extreme temperatures were not obvious (Sen's slope estimate is 0). The mutation points range from 1981 to 2002 and the mutation point of extreme rainfall series is earlier than that of extreme temperatures. Compared with the GEV model, the parameters of the GPD model show a smaller variation before and after climate change, and the extreme meteorology values corresponding to the same recurrence period show a decreasing trend after climate change. The performance of GEV and GPD models after climate change is generally more fit than that before climate change.

Highlights

It is well known that the global climate has been changing over the past century
The Heuristic segmentation method is used to diagnose the mutation point of the extreme meteorology series, and the mutation point determines the time point at which climate change starts to affect extreme meteorology. the time series before the mutation point is considered as the series that has not been affected by climate change and named it as the pre-climate change series, whereas the time series after the mutation point is considered as the series that has been affected by climate change and named it as the post-climate change series
(3) Climate change has an impact on the relationship between climate indices and extreme meteorology

Summary

Introduction

It is well known that the global climate has been changing over the past century. According to the fifth report of the IPCC (Intergovernmental Panel on Climate Change), the global average surface temperature rose by 0.85 °C from 1880 to 2012, and the warming rate (0.12 °C/10a) of the global average surface temperature from 1951 to 2012 was almost twice since 1880 (Shen & Wang 2013). The warming of the climate system leads to the increasing frequency and intensity of extreme temperature and precipitation events (Tian & Yang 2017). Climate change can impact the vegetation (Berdimbetov et al 2021). In Xinjiang, climate change leads to reduced rainfall, which exacerbates the survival of endangered plants (Khan et al 2021)

Methods

Results

Conclusion