Study of the Impact of an Intense Biomass Burning Event on the Air Quality in the Eastern Mediterranean

Abstract

Aim of this work is to study the impact of the intense forest fires that tookplace in Greece at the end of summer 2007 on the air quality in the Eastern Mediterranean. For this reason the meteorological model MM5 and the photochemical model CAMx are applied over the study area with 10 km spatial resolution. CAMx model is implemented for two emission scenarios; with and without biomass burning emissions. High spatial resolution wildfire emission data are used that are based on the Global Fire Emissions Database (GFED3). The CAMx chemical boundary conditions are taken from the TM4 global model. The nonradiative impact on the composition of the atmosphere and on environmental indices (e.g. Aggregate Risk Index) is quantified in regional scale. The impact of the atmospheric processes on the air pollution levels due to the biomass burning event is also studied giving more emphasis on the boundary layer. The intense biomass burning event in the Eastern Mediterranean at the end of August 2007 results in an enhancement of the CO, NOx and PM2.5 concentrations over almost all the study area, which can range from several times to two order of magnitude over the fire hot spots. The increases in O3 levels are less pronounced and are found mainly downwind the burnt areas. On the 25th August 2007, when fire counts in the study area are maximum, in the daytime boundary layer, the inclusion of biomass burning emissions results in a change of the chemical regime from O3 destruction to O3 production.