A Case Study for Ahmedabad City, India Using Envi_met Model to Evaluate the Urban Climate and Thermal Sensation in a High-Density Urban Environment

For the past many years, the research group’s top priority has been to better understand the urban heat island effect and to develop sustainable cities with a clear path towards heat mitigation techniques. This problem is typically observed in urban areas where rising global warming is changing the climate and raising the earth’s surface temperature. As a result, this research study seeks to explore several heat mitigation techniques for enhancing outdoor thermal comfort in a large-scale urban environment by taking into consideration a residential + commercial area from Kalupur near Ahmedabad railway junction, Ahmedabad City, Gujarat, India. Which has an administrative boundary of 89,700 m² = 0.09 m² was modelled in Envi_met (SPACES) V5.0.2 software. As Ahmedabad city has been considered for the research study, which is classified as hot, semi-arid climate-Bsh based on Köppen climate classification and aim of the study is to improve the outdoor thermal comfort and to plan heat mitigation strategies of an Ahmedabad city, Gujarat, India, with analyzing mean radiant temperature (Tmrt) and Air Temperature (AT) with the application of ENVI-met V5.0.2 Software. The input data for the simulations process are based on the meteorological station and downloaded from visual crossing website. In this paper, a residential + commercial area of 0.09 m² which is located at latitude (N°, −S) = 23.03 and Longitude (W°, + E) = 72.60 in Ahmedabad city were analyzed for the hottest day which has an extreme condition of heat stress in area. The selected day for simulation was 15th May 2022 with maximum Ta 45 °C. Based on simulation of modeling the four different case scenarios in ENVI-met (SPACES) model for a hot summer day in May. The simulated results (for a typical Summer on 15th May 2022 at 15:00 & 5:00 AM) show that the suggested strategies have an effect on OTC. The results are provided in both spatial and temporal terms. It means adopting case-3 (clustered arrangement of tree (N, S, E, W and Middle) with 20% increasing in green cover) and case-4 (no trees but only grass means green ground near the building) in particular location can reduce the Ta around 0.852 to 2.052 °C with Tmrt reduce up to 2.044 °C in summer at 15:00 and the results are validated through a field measurement and software simulations. Comparisons using statistical metrics of R², d, and RMSE which have value (RMSE = 0.079, R² = 0.80 and d = 0.895).