Abstract

The development of the Delhi Mumbai Industrial Corridor (DMIC) region is India’s most ambitious project that is witnessing rapid urbanization growth. Another critical environmental issue faced by this region is climate change. This article investigates the possible impacts of urbanization and climate change in the DMIC region on near-surface air temperatures in the month of May, which is typically the hottest month of the year with the highest heat stress. Numerical experiments were carried out using the Weather Research and Forecasting (WRF) model to estimate the impacts of three urbanization scenarios and four future climate scenarios (Representative Concentrative Pathway [RCP] 4.5 and RCP8.5 mid- and end-century). This allows for a quantitative evaluation of the impacts of urbanization relative to the impacts of climate change as well as a preliminary estimate of impacts of urbanization under future climate conditions. Results of the numerical experiments show that urbanization can increase the minimum temperature by more than 3°C, but the effect on maximum temperature is small. This impact is mainly due to changes in the surface energy budget, where increased heat capacity and reduced evaporation lead to a 20 to 30 W/m2 increase in sensible heat flux and a 12 to 18 W/m2 reduction in latent heat flux. Climate change increases both maximum and minimum temperature by up to 4°C. The combined impact of urbanization and climate change is found to be severe, with the minimum temperature showing an increase of approximately 4 to 7°C and the maximum temperature showing an increase of approximately 1.5 to 3.5°C. Overall, urbanization is likely to exacerbate the adverse effects of climate change in the DMIC region.