Identification and Assessment of Seasonal Trends of Meteorological and Agricultural Droughts – A Case Study of Southern Districts of Khyber Pakhtunkhwa (Pakistan)

Abstract

One of the worst climatic extremes the globe has experienced in recent years is drought. The present study is conducted over the southern districts of Khyber Pakhtunkhwa, Pakistan as this region is heavily dependent on rainfall, and the deficiency of seasonal rainfall is one of the major causes of drought in this area. The Global Precipitation Climatological Centre (GPCC) and Climate Research Unit (CRU) have employed observational and monthly gridded temperature and precipitation data sets to ascertain the seasonal (winter and summer) and annual meteorological drought from 1990 to 2020. Five different drought indices, including the Standardized precipitation Index (SPI), the Reconnaissance Drought Index (RDI), the Deciles Index (DI), and two relatively new drought indices (aSPI and eRDI) based on effective rainfall using the United States Bureau of Reclamation (USBR), have been calculated in order to determine the consensus of drought years. These drought indices identified six seasonal drought years i.e. 2000, 2002, 2009, 2014, 2017, and 2018 for summer season and 2000, 2001, 2007, 2011, 2017 and 2018 for winter season, whereas all the five indicators together showed that the years 2002 and 2018 were the most severe drought years in the region. In each of the drought years, to determine the effects of seasonal drought due to meteorological factors over agriculture, a geographical analysis of the Normalized Difference Vegetation Index (NDVI) was conducted where more than 60% of the region experienced a drought in agriculture during winter over southern districts of Khyber Pakhtunkhwa, Pakistan. The overview provided by this study will help drought managers and disaster agencies create a climate wise agriculture contingency plan that will lead to sustainable growth throughout the region.