1- Department of Physical Geography, Faculty of Geography, University of Tehran, Tehran, Iran
2- Department of Physical Geography, Faculty of Geography, University of Tehran, Tehran, Iran , Mostafakarimi.a@ut.ac.ir
Abstract: (91 Views)
Drought is one of the most significant natural hazards, characterized by complex spatiotemporal patterns. This study analyzes the structural and spatial characteristics of droughts in Iran across three temporal scales: annual, seasonal, and monthly. To achieve this, the intensity and extent of droughts were calculated using the RAI index and ERA5 monthly precipitation data over 42 years (1979–2021). Initially, the spatial distribution and directional trends of the drought centroid were examined, and its spatial variations over the years were analyzed. Additionally, the relationship between the location of the drought centroid and its extent was investigated. The results revealed that during the cold season, the drought centroid is primarily concentrated in central Iran, while in the warm season, it shifts toward the northwest, the Caspian Sea coast, and the southeastern regions of the country. The distribution pattern of droughts at all scales predominantly follows a northwest-to-southeast trajectory. Furthermore, shifts in the drought centroid toward the northeast, east, southeast, and south were observed to coincide with an increase in drought extent, whereas shifts toward the north, northwest, and west were associated with a reduction in drought extent. Overall, the findings of this study demonstrate a direct relationship between the location of the drought centroid and changes in drought extent, despite the fact that droughts in Iran lack consistent and predictable spatiotemporal patterns
Type of Study:
Research |
Subject:
Special Received: 2025/01/6 | Accepted: 2025/09/3