Identification and Assessment of Seasonal Trends of Meteorological and Agricultural Droughts - A Case Study of Thal Region, Punjab Pakistan

Abstract

Drought is a natural phenomenon mainly caused by below-average precipitation over an extended period. The present study is conducted over the Thal Region of Pakistan as it is dependent upon rainfall as there are very less surface water resources for Agricultural activities. So deficiency of seasonal rainfall is one the major reason of drought in this region. The observational as well as monthly gridded data sets of Global Precipitation Climatological Centre (GPCC) and Climate Research Unit (CRU) of precipitation and temperature have been used to Identify the meteorological drought both seasonal (Rabbi and Kharif) and annual for study period of 1960 to 2019. In order to determine the consensus of drought years, five different drought indices i.e., Standardized precipitation Index (SPI), Reconnaissance Drought Index (RDI), Deciles Index (DI) and two relatively new drought indices (aSPI and eRDI) based on effective rainfall by using United State Bureau of Reclamation (USBR) have been calculated. These drought indices identified six seasonal drought years (2000, 2002, 2004, 2006, 2007 and 2018), whereas the entire five indices showed a consensus that 2000 and 2002 were the most severe drought years over the region. In order to identify the impact of meteorological seasonal drought over agriculture, the Normalized Difference Vegetation Index (NDVI) was analyzed spatially in each of the drought years where above 50% of the total area was under agriculture drought during Kharif even all the drought years have more than 17 % of extreme drought over Thal Region. This study provides an overview for the drought managers and disasters agencies to develop contingency plan of climate smart agriculture towards sustainable development over the region.