Drought similarity analysis based on intensity-duration-area characteristics

Abstract

[Objective] Droughts are characterized by their slow onset and widespread impacts, posing significant threats to water resources, agriculture, and energy. Climate change has increased the frequency of droughts and thus it is important to deepen our understanding of drought impact assessment, for which the similarity analysis of droughts based on historical events is a useful tool. [Methods] Based on daily precipitation and monthly temperature data from ERA5 in Yunnan Province for the period 1980—2021, this study analyzes drought intensity, duration, and coverage area, and proposes a method for drought similarity analysis. Firstly, the run theory is employed to analyze the intensity, duration, and coverage area of historical droughts. Secondly, the 2019 drought event is selected as the case study to evaluate its evolutionary process. Finally, the distances of different characteristics between the 2019 drought event and other historical droughts in Yunnan Province are calculated for similarity assessment. [Results] By conducting the similarity assessment of the 2019 drought event and comparing the spatial variability, results show that the similarity between the targeted drought event and identified drought events is high(with a similarity measure of over 80%). [Conclusion] The drought similarity assessment method proposed in this study combines intensity, duration, and coverage area of drought events and performs well in identifying similar drought events, which can provide technical support for drought disaster assessment.

Keywords

drought / drought characteristics / similarity / Yunnan / climate change / spatiotemporal changes / precipitation / water resource