High resolution modelling of anthropogenic heat from traffic in urban canopy: A sensitivity study

Impact of climate change is often amplified in urban areas — particularly during the heat waves, the extreme temperatures are even more pronounced in cities due to the effect urban heat island (UHI). It is therefore important to improve our understanding of heat fluxes and energy balance in urbanized areas. We investigate the possibility of high resolution urban canopy modelling using PALM model. To account for the realistic implementation of urban canopy processes in complex urban geometry we enhanced PALM model including some of the most important urban canopy mechanisms including detailed description of physical properties of urban surfaces, calculation of shape view factors and plant canopy sink factor to model accurately both shortwave and longwave radiation budgets, and heat transfer within urban surfaces and on the interfaces of surfaces and atmosphere or ground. Such approach allows for very detailed modelling in high spatial and temporal scale. The simulation of the impact of anthropogenic heat from transportation has been conducted as one of the pilot experiments to test feasibility of this approach and also sensitivity of highly unstable turbulent flow heat exchange to a relatively small perturbation of input parameters.