Desertification of Bengal Dryland Areas Possible under Projected Climate Conditions.

Abstract

Drylands are some of the most sensitive areas to climate change and human activities around the globe. Assessment of future climate trend scenarios provides valuable practical information for dryland management decision-making. According to Huang et al. (2016), more than 50% of global drylands will expand by this century, with a maximum (78%) of newly expanded dryland occurring in developing countries. To understand the potential for expansion of drylands and desertification, we examine critical predictor variables (temperature and precipitation) of Bengal dryland expansion to guide early actions to mitigate and prevent desertification. Using trend analysis of biascorrected CMIP6 projected climate change data for temperature and precipitation (2022-2041), results indicate that future dryland expansion is possible from increases in temperature and declines in monsoonal precipitation. Over the next two decades (2022-2041), Bengal dryland areas will be +0.1 to +0.5 °C warmer and rainfall will decrease by -2.57 to -13.43 mm total during the monsoon period. Given that these variables are critical predictors of dryland expansion due to their role in driving evapotranspiration and soil moisture deficits, we anticipate an increase in the population affected by water scarcity, land degradation and desertification may be a potential outcome. Our work provides information critical for effective dryland management, biodiversity conservation, and land-use planning under future climate conditions.