Analysis of the Urban Energy Balance in Bahía Blanca (Argentina)

Abstract

The objective of this study is to define the effect of Bahía Blanca (Argentina) urban form and function on heat fluxes integrated in its energy balance at a local scale. The most frequent Local Climate Zones (LCZs) were identified in Bahía Blanca. Most of the LCZs are built types, corresponding to LCZ 1 and 2 in the microcenter, LCZ 3 in the macrocenter, and LCZ 6 and 9 in the city peri-urban area. The spatial distribution of Urban Energy Balance (UEB) was analyzed by calculating indices: the sensible heat index (χ), the evaporation index (γ), the storage index (Λ) and Bowen ratio (β). In the city central sectors there is a preponderance of sensible heat fluxes warming the atmosphere closest to the surface. Bahía Blanca estuary has the highest latent heat flux magnitudes, followed by coastal areas and islands associated. Peri-urban land surfaces and suburbs have greater magnitudes of latent heat flux since they are composed of a high percentage of permeable surfaces. A marked variability is observed in the daytime and nighttime QF anthropogenic heat fluxes, with maximums during the day. During the night, QF values decrease in magnitude throughout the urban area.