Spatiotemporal characteristics of drought events in Asia from a three-dimensional perspective

With global warming and rising of natural hazard incidences, more countries are paying attention to prevent or delay these events. As one of the most important natural hazards, drought has profound impact on socio-economic development and livelihoods. It is therefore crucial to understand the spatiotemporal characteristics and trends of droughts. In this paper, an improved three-dimensional clustering algorithm was used to identify and predict drought events based on CMIP6 data, utilizing parameters such as severity, intensity, affected area, duration, centroid changes, and migration paths of large-scale drought events in Asia. The results showed that: (1) duration of drought events in Asia predominantly lasted two months and were more pronounced in West Asia, Central Asia, and South Asia. As carbon emission scenarios intensifies, the frequency and severity of drought showed an upward trend. (2) 1.55% of the total area was found to be within the optimal threshold for drought patch area. Drought migration in Asia was mainly in the east-west direction, and the migration distance was expected to increase significantly, especially under SSP5-8.5 scenario. (3) Large-scale drought events are often prone to aggregation and fragmentation. The central and western regions of Asia frequently experience droughts, which can lead to extensive and prolonged severe drought sequences. This study provided a new perspective for understanding three-dimensional characteristics of drought events in Asia, which is important for predicting and responding to future drought risks.