Assessment of the impact of urban tree canopy on microclimate in Bhopal: A devised low-cost traverse methodology

Abstract

The following study was taken to quantify the potential of tree canopy in reducing temperatures. The study locations (parks, forests, plantations) with micro-meteorological observation plots were stratified in the water proximity zones. The mobile traverse was adopted in the locations to collect the data on summer days of May and June 2016. To overcome time-lag induced temperature changes among the measurement days, the ambient temperature of day 1 of the survey was used as base temperature to correct the errors. Hourly rates of temperature change under different tree canopy densities were used to correct the time-lag induces temperature change at the plot level. Apparent temperature of the study plots was regressed against the tree canopy density of the plot, distance from water body, distance from road, and size of the green space the plot was located in. The results of linear regression depict that dense tree canopies reduces apparent temperature by 2.5 °C in the tropical dry summer season. The methodology compensates for lack of multiple meteorological stations in the city that would allow simultaneous measurements and error corrections. Tropical cities like Bhopal can experience similar microclimate amelioration when urban tree canopy is incorporated in the urban planning and design.