Characterization of seasonal droughts in Balochistan Province, Pakistan

摘要

Droughts are usually destructive when they coincide with crop growing season. Cross-seasonal drought characterization can better inform drought mitigation efforts. The present study relies on precipitation data from the Global Precipitation Climatology Centre to reconstruct historical droughts during different climatic seasons in Balochistan province, Pakistan. We identified seasonal drought events based on the standardized precipitation index for each season. The distribution of reconstructed drought events was analyzed to determine their seasonality and to calculate their return periods. Using these return periods, we constructed seasonal drought maps. The study revealed that early winter droughts are frequent in the north of Balochistan, where the return periods of moderate, severe, and extreme droughts are 7, 21, and 55 years, respectively. Severe and extreme late winter droughts are more frequent in the upper north, with return periods of 16 and 35 years, respectively. Early summer droughts occur more frequently in the east, returning every 8, 20, and 60 years; late summer droughts occur in the northeast, with moderate, severe, and extreme droughts returning every 8, 22, and 65 years, respectively. Rabi droughts are more frequently in the central and northeaster regions of Balochistan, while more severe kharif droughts occur primarily in the eastern regions. These seasonal droughts were found to be positively correlated with variations in the seasonal rainfall throughout the study area. The findings of this study contribute to our understanding of seasonal drought characteristics and help to inform drought mitigation planning.