Drought: A critical review of different perspectives under changing climate

Abstract

The phenomena of drought are intricate and multifaceted, impacted by various Physical and Biological mechanisms and processes. Because of this intricacy, it is very complex to explain cause and effect in a straightforward manner, which makes researching drought and climate change difficult. Here, we summarize significant recent developments in our knowledge of drought dynamics based on different perspectives including Precipitation, Evaporation, Soil Moisture, and Drought indices under changing climate. Forecasts from models suggest that precipitation is expected to rise in most terrestrial areas, except in subtropical regions where it is anticipated to decline due to increasing greenhouse gases. The frequency of light to moderate precipitation is projected to decrease over most regions of the world. Prognostic model outputs, as opposed to offline drought metrics, should ideally be used to evaluate variations in soil moisture wetness and dryness in the future and to interpret the results within the framework of the linked soil-vegetation–atmosphere system. It is important to prioritize the resilience of indices when temperature and other drought-triggering variables change frequently as they are based on different assumptions and behave differently to the same level of Global climatic Fluctuations. Creating drought indices in a warming climate without taking into account the factors that control the underlying conditions like climatic data accessibility, downscaling methods, potential evapotranspiration (PET) calculation, baseline period, and nonstationarity could lead to uncertainty. Additional obstacles to a trustworthy drought assessment under certain circumstances may include anthropogenic factors, climate data resolution, and non-stationary climate.