Satellite-based (2000-2015) drought hazard assessment with indices, mapping, and monitoring of Potohar plateau, Punjab, Pakistan

Drought is one of the deadly natural disasters that leave tearstained faces and broken dreams in its wake. Lifecycle as we know it comes to a halt during a dry season in a region. The purpose of this study was to observe the temporal and spatial variation of droughts in the rain-fed area of Potohar plateau (22,254 km(2)), Punjab, Pakistan, from 2000 to 2015, through remotely sensed satellite data, available at the database of Google Earth Engine. Potohar consists of four major districts of the country; Chakwal, Attock, Rawalpindi, and Jhelum. From 2000 to 2015, indices calculated were: standard precipitation index (SPI), standard precipitation evapotranspiration index (SPEI), vegetation condition index (VCI), precipitation condition index (PCI), soil moisture condition index (SMCI), and temperature condition index (TCI). In this study, SPI and SPEI pointed out meteorological droughts in 2000, 2001, 2002, 2004, 2009, 2010, and 2012, which were taken as base years for drought in the study. The study concluded that the main factor involved in the drought severity is not one, but rather a combined accumulation of temperature, precipitation, and soil moisture. Soil moisture and precipitation affect the vegetation in the area more so than the temperature of the land surface. Soil moisture was heavily influenced by the amount of precipitation. The land surface temperature was seasonal dependent. The surface temperature was warmest in Chakwal and Attock, while Rawalpindi had the coldest land surface temperature. Soil moisture increased with precipitation. Soil moisture was high in Rawalpindi and Attock during drought years.