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List of Abstracts 135We will present the lidar measurement results for two large fires in northwestern United States: the KootenaiCreek Fire in western Montana on August 27–28, 2009, and the Tripod Complex Fire in central Washingtonon August 8–21, 2006. We will show the profiles of multiple layers of smoke plumes, the upper and lowerboundaries of the plumes, and their spatial and temporal evolution. The selected profiles of aerosolbackscattering, extinction coefficients, and optical depth will also be presented. The profiles are derivedfrom the lidar data using the lidar measurement methodology adapted to the specifics of smoke-pollutedatmospheres. In addition, we will show a time series of the progression of smoke plume dynamics, itsinteraction with clouds, and its diurnal cycle from early morning to late afternoon for the I-90 Fire in westernMontana on August 9–16, 2005. The lidar observations are being used to validate the plume rise sub-modelsin our air quality-forecasting model, Weather Research and Forecasting – Smoke Dispersion (WRF-SD).P-Transformation.24 ID:4187 10:30NO x and PAN emissions from biomass burning: Implications for tropospheric ozoneMatthew Alvarado, Jennifer LoganHarvard UniversityContact: mjalvara@seas.harvard.eduAircraft campaigns in the Arctic (e.g., ARCTAS-B) and in the tropics (e.g., TRACE-A) have shown that theNO x emitted by biomass burning is rapidly converted to PAN within the concentrated smoke plumes.However, most emission inventories used in global models do not account for this subgrid chemistry, thusoverestimating NO x emissions and underestimating PAN emissions from biomass burning. This can have alarge impact on the simulation of tropospheric chemistry, especially ozone, in regions impacted by biomassburning. Here we examine the impact of these emissions of PAN on global tropospheric chemistry using theGEOS-Chem model. We use observations from TES and OMI as well as aircraft data to evaluate the modelsimulations. In the Arctic, aircraft and TES observations during ARCTAS-B both show little evidence forozone formation within boreal smoke plumes. Adjusting model emissions to match aircraft observations ofCO and the observed enhancement ratios of NO x and PAN in boreal smoke plumes reduces model ozone by5% throughout large regions of the Arctic. We will discuss the impact of PAN emissions from tropicalbiomass burning on ozone levels, and the sensitivity of model ozone to the injection height of emissions.P-Transformation.25 ID:4491 10:30FOREST FIRE IMPACT ON AIR QUALITY: THE LANCON-DE-PROVENCE 2005 CASESusanna Strada 1 , Celine Mari 1 , Jean-Baptiste Filippi 2 , Frédéric Bosseur 21 UNIVERSITY OF TOULOUSE / CNRS / LABORATOIRE AEROLOGIE, TOULOUSE, FRANCE2 UNIVERSITE OF CORTE / CNRS / SPE, CORTE, FRANCEContact: celine.mari@aero.obs-mip.frIn Mediterranean regions, forest fires are a risk to the environment and to communities. Wildfires alsorepresent a significant source of gas and aerosols. Depending on the meteorological conditions, theseemissions can efficiently perturb air quality and visibility far away from the sources. The aim of this work isto simulate the interactions of a mediterranean fire with its environment both in terms of dynamics and airquality. A new coupled fire-atmosphere system Forefire / Meso-NH was applied for the first time to a typicalmediterranean fire to study the impact of fire on the dynamics and air quality. The coupled atmospherewildfiremodeling was able to simulate well documented perturbations induced by forest fires on theatmosphere, in particular fire-induced increase and convergence of surface winds. The impact of fire onatmospheric pollutants was simulated several hundreds of kilometers downwind of the burnt area. Ozonedestruction was obtained near the fire in the high-NOx regime whereas ozone production was simulatediCACGP-IGAC 2010 14 July, 2010