Evaluation of urban development impacts on the microclimate variations in tropical cities

Abstract

Urban forcing on the overlying atmosphere varies over a wide range of scales, developing intense urban-atmosphere interactions resulting in the generation of small-scale, intense, and highly unpredictable climatic systems. The advantages of numerical weather prediction (NWP) models to understand the land–atmosphere interactions and their ability to dynamically downscale coarser resolution global climate products integrated with higher resolution surface parameters has been a widely accepted approach in studying this process. However, the accurate representation of urban morphology is critical in improving the potential of mesoscale NWP models like WRF (Weather Research and Forecasting) to simulate the micro-climatic conditions over the cities more precisely. This study adopted a two-city approach to analyse the urban–atmosphere interactions in the case of the complex tropical region by selecting two dimensionally different cities, i.e., Kolkata and Guwahati, which also differed in terms of urban intensity. Both cities are situated on the most active monsoon belt of the Indian sub-continent, which also has significant influence on their regional climatology.