A numerical experiment to study the impact of temperature enhancement by anthropogenic heating on local weather at the Angul region of India

Abstract

The present study mainly focuses on the effect of temperature enhancement on local weather due to the heat emitted from anthropogenic sources with a numerical weather prediction model. In this study, anthropogenic heat (AH) flux is mainly considered as heat generated due to industrial action in the urban area. Angul district located between 20.41�21.80�N latitude and 84.55�85.30�E longitude in the Odisha state of India is chosen as the study region. In this location, a heavy rain event on 16 August 2008, and a light rain event on 22 March 2008 were identified. In the first part of this study, numerical simulations are performed using the mesoscale weather research and forecasting (WRF) model for both the rain events, based on which the near-surface rain rate is simulated. The simulated rainfall is compared against tropical rainfall measuring mission (TRMM) precipitation radar observations qualitatively for validation purposes. The comparative study throws a lot of insight based on different physics options available in the WRF model. The study found that the WRF double moment, 6-class microphysics scheme is better in capturing both the rain events in 2008. The TRMM validated WRF simulation now constitutes the control run against which comparisons for other cases are made. In the second part, a numerical experiment is performed to understand the effect of AH on local weather for the same region. The temperature at the surface level is perturbed by increasing it by 10?K near the industrial site and exponentially decreasing with a height up to the atmospheric boundary layer. The design of the numerical experiment is such that the sensible heat, latent heat and moisture parameters are affected by changing the temperature parameter alone. The result shows that the rainfall rate increases locally for both the events due to the increase in temperature at the industrial site. The rate of increase in heavy rain event is nearly twice whereas, in light rain, it was found to increase by 1.7 times. In the third and final part of the study, the flow pattern at the near-surface level is studied in and around the industrial zone, and the same is then compared with the perturbed case for both the rain events. In the perturbed cases, the difference in temperature in and around the region causes pressure differential leading to the formation of stronger wind. � 2022, Indian Academy of Sciences.