Research on drought risk in Xiong’an New Area under climate change

Abstract

The Xiong'an New Area is located in the central part of the North China Plain, which is characterized as one of the regions in China with relatively scarce water resources. The evolution of its drought characteristics is deemed significant for the economic and social development of the Xiong'an New Area and effective water resource management. Long-term meteorological monitoring data from 31 weather stations from 1975 to 2018 and CanESM2 climate model data were utilized to calculate the Standardized Precipitation Index(SPI) across various time scales. Additionally, different types of Copula functions were employed to construct a two-dimensional joint probability distribution model based on the characterization of drought features. The aim was to analyze the drought evolution patterns and risk status in the secondary water resource zone where the Xiong'an New Area is located under the influence of climate change. At both monthly and seasonal scales, a spatial redistribution of the frequencies of mild, moderate, and severe droughts has been observed in the secondary water resource zone, although the overall changes remain minimal. In contrast, a significant increase in the frequency of extreme drought events has been recorded. On the annual scale, while a decrease in the frequency of moderate droughts has been noted, significant increases in the frequencies of mild, severe, and extreme droughts have been observed, along with notable shifts in their spatial distribution characteristics. The Clayton Copula function was found to provide the best fit for drought duration and intensity in the region. The univariate return periods for these variables are situated between the joint return period and the co-occurrence return period; as the return period extends to 100 years, a drought duration of 6.9 months and a drought intensity value of 7.4 have been reached, while the co-occurrence return period exceeds 200 years. The results indicate that a marked clustering of mild, severe, and extreme drought events is expected to occur in the Xiong'an New Area and its surrounding regions. This suggests an increased potential risk to the water resource carrying capacity in the future, while the probability of prolonged high-intensity drought events remains relatively low.

Keywords

Xiong'an New Area / climate change / drought / joint probability distribution