Ozone production from the interaction of wildfire and biogenic emissions: A case study in Russia during spring 2006
- ISSN: 16807316
- DOI: 10.5194/acp-12-7931-2012
The objective of this study is to investigate the contribution of\nbiomass burning emissions to O-3 production during small-scale dry-grass\nfires over Western Russia (24 April-10 May 2006) as well as to quantify\nthe effect of biogenic emissions in this environment. By using the\nFactor Separation methodology, we evaluate the pure contribution of each\none of these two sources and we appoint the significance of their\nsynergistic effect on O-3 production. The total (actual) contribution of\neach source is also estimated. Sensitivity simulations assess the effect\nof various fire emission parameters, such as chemical composition,\nemissions magnitude and injection height. The model results are compared\nwith O-3 and isoprene observations from 117 and 9 stations of the EMEP\nnetwork, respectively.\nModel computations show that the fire episode determines the sensitivity\nof O-3 chemistry in the area. The reference run which represents grass\nfires with high NOx/CO emission ratio (0.06) is characterized by\nVOC-sensitive O-3 production. In that case, the pure impact of fire\nemissions on surface O-3 is up to 40-45 ppb, while their synergistic\neffect with the biogenic emissions is proven significant (up to 8 ppb).\nUnder a lower NOx/CO molar ratio (0.025, representative of agricultural\nresidues), the area is characterized by NOx-sensitive chemistry and the\nmaximum surface O-3 predictions are almost doubled due to higher O-3\nproduction at the fire spots and lower fires' NO emissions.