Correlation between pollution levels and city design: How different building and vegetation scenarios affect air pollution at Fabriksgatan, Gothenburg — for different wind configurations and emission scenarios
Examensarbete för masterexamen
Industrial ecology (MPTSE), MSc
Air pollution threat public health, the environment and objects of cultural value. It also affects the climate and is a big problem in many cities. It is therefore of interest to design cities in such a way that pollution levels are low. Pollution levels could be decreased via dispersion (when pollutants are diluted) and deposition (when pollutants deposit at surfaces). This report study how shape and size of buildings and different vegetation scenarios (one with just background vegetation; one with a sparse row of English oaks and background vegetation; one with a dense row of English oaks and background vegetation; and one with a green wall made of ivy and background vegetation) affect pollution levels of NO, NO2, O3, PM10 and PM2.5 for different wind configurations and emission scenarios for a specific area. The area is Fabriksgatan in Gothenburg and its surroundings. Two different street canyon widths are studied: one representing the width today and one wider, with room for a bike- and walkway and a row of trees. For this, the large eddy simulation (LES) model PALM, based on Fortran-code, is used. The main findings are that a wide street canyon enables more circulation and thus lower pollution levels. Small point houses open up the street canyon and such configurations have lower pollution levels than more confined street canyons. Both buildings and vegetation could be used to shield out emissions, but vegetation generally increases mean concentrations. This is believed to be due to an incomplete implementation of the effects of deposition in PALM. Thus, the effects of deposition must be studied in more detail before general advice on vegetation could be made.
Air pollution , urban vegetation , city design , large eddy simulation , PALM