Estimation of the Spatio-Temporal Characteristics of Anthropogenic Heat Emission in the Qinhuai District of Nanjing Using the Inventory Survey Method

Taking the Qinhuai District of Nanjing, China, as the study area, this research adopted the bottom-up energy inventory method to estimate the anthropogenic heat emission at the spatial resolution of 100 m during the daytime and nighttime. Land use data derived by the visual interpretation from high resolution imagery was combined with the field investigation as well as statistical population data to estimate the spatial distribution of the population, which was then used to calculate the human metabolism. The traffic heat emission estimation was mainly based on the interpretation of different levels of roads and the statistical vehicle volume from field video recordings. The spatialized population, the collected energy consumption statistical data, the corresponding function and the number of floors in the buildings were combined to compute the industrial and the building heat emissions, respectively. The results illustrate the detailed spatio-temporal distribution variances of each type of anthropogenic heat emission during the daytime and the nighttime, which show a higher reasonability and precision. During the daytime, the high intensity of anthropogenic heat emissions is mainly distributed in the southwest of the study area, while the heat intensity is uniformly distributed during the nighttime. The average anthropogenic heat flux densities are 33.45 W/m(2)and 15.34 W/m(2)in the daytime and the nighttime, respectively. The highest heat flux density with the value of 14.93 W/m(2)is released by commercial buildings during the daytime, while the traffic heat is the highest with the average value of 5.17 W/m(2)during the nighttime.