关键词: 气象干旱;水文干旱;农业干旱;干旱风险;Copula函数;滇中引水工程;滇中高原;

Abstract: The Central Yunnan Plateau region is a key area for the social and economic development of Yunnan Province, but it is also the region most prone to drought disasters.Investigating the drought characteristics and risks in this region is crucial for regional drought defense.A comprehensive drought index MDI was constructed using the multivariate Copula function to identify comprehensive drought events that contain meteorological, hydrological, and agricultural drought characteristics, and to determine the overall drought characteristics of the Central Yunnan Plateau region.Based on the drought characteristics analysis, a risk assessment method for drought disasters was proposed based on natural disaster risk theory.The drought risk levels were divided into four categories based on the level of danger, implantation rate, affected rate, and water shortage rate, and the impact of the Central Yunnan Water Transfer Project on regional drought was evaluated.The results reflected:(1) The overall drought characteristics of the Central Yunnan Plateau are that the drought duration was 1.90～5.10 months, the intensity was 2.80～4.50,and the joint return period was 2.45～3.14 years.The regional distribution of drought duration, intensity, and joint return period were longer/stronger in Chuxiong, Kunming, and Yuxi that were in the central area, and Honghe in the south, while they were shorter/weaker in Dali in the west and Qujing in the east.After the completion of the Central Yunnan Water Transfer Project, the regional drought showed a development trend of shorting in duration, weakening in intensity, and prolonging in joint return period.(2) Before the Central Yunnan Water Transfer Project, the drought risk level in the central plateau region was generally 4～7 levels.After the completion of the project, the drought risk level generally decreased by 1～4 levels, resulting in a significant reduction in drought risk.This suggests that by building a water network in the Central Yunnan Plateau region through the Central Yunnan Water Transfer Project, the region′s ability to defend against drought disasters can be improved, which is beneficial to the sustainable and stable development of the regional economy.

Key words: meteorological drought; hydrological drought; agricultural drought; drought risk; Copula function; Central Yunnan Water Transfer Project; Central Yunnan Plateau;