Analysis of Hot and Dry Weather Events in Iran During the Period 1986–2023

Articles in Press

Document Type : Research Paper

Authors

1 tabriz uni

2 Department of Climatology and Urban Planning, Faculty of Planning and Environmental Sciences, University of Tabriz, Tabriz

3 Department of Climatology and Urban Planning, Faculty of Planning and Environmental Sciences, University of Tabriz, Tabriz,

4 Department of Climatology, Faculty of Natural Resources, University of Kurdistan, Sanandaj, Iran

10.22034/gp.2025.69594.3464

Abstract

Objective: This study investigated the spatial distribution of hot and dry weather events across Iran from 1986 to 2023.

Methods: Hourly temperature and relative humidity data from 31 synoptic stations were analyzed. Synoptic patterns associated with hot and dry conditions were identified using NCEP/NCAR reanalysis data at four pressure levels (surface, 850, 700, and 500 hPa). To validate the observational findings, land surface temperature (LST) products derived from the MODIS sensor onboard the Aqua satellite were employed. The HYSPLIT model was also applied to trace the source and trajectory of the air masses contributing to the hot and dry conditions. Moreover, factor analysis and principal component analysis (PCA) were conducted to determine the underlying drivers and dominant components influencing the intensity and frequency of hot and dry weather events in this region. Results: The analysis showed that hot and dry weather events (HDWEs) were most intense in the eastern and southwestern regions of Iran, especially Khuzestan Province, whereas coastal and mountainous areas experienced milder conditions owing to the moderating effects of the Caspian Sea and Persian Gulf. The highest temperatures and lowest relative humidity occurred at approximately 12:00 UTC. Synoptic and trajectory analyses indicated that the subtropical high-pressure ridge dominated most of Iran, and hot and dry air masses originated from both domestic and external sources.

Conclusions: Overall, HDWEs in Iran are primarily controlled by the interactions among topography, surface moisture, and large-scale circulation patterns. Factor and principal component analyses confirmed that thermal and moisture gradients, geographical position, and seasonal variability are key drivers of Iran’s hot and dry climate regime. These findings enhance our understanding of the atmospheric dynamics influencing HDWEs and provide a foundation for improving regional climate prediction and adaptation planning.

Keywords

Main Subjects

Journal of Geography and Planning

Articles in Press, Accepted Manuscript
Available Online from 11 November 2025

Files

Share

How to cite

Statistics