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List of Abstracts 102measurements from aircraft campaigns and ozonesondes. Both satellite retrievals generally reproduce broadfeatures in the upper troposphere such as the wave-one pattern. However, these comparisons reveal highbiases in both the ACE-FTS (17-23%) and OSIRIS (12-25%) ozone relative to aircraft and ozonesondeobservations. We demonstrate that the ozone production efficiency in the upper troposphere can bedetermined using ACE-FTS O3 and HNO3 measurements. The resulting value of 120±11 mol/mol is inbroad agreement with model simulations indicating the capability of satellite observations in the tropicaltroposphere to provide insight into ozone production.P-Observations 1.31 ID:4576 15:35The observing requirements for the prediction of ozonePaul Hamer 1 , Kevin Bowman 1 , Daven Henze 21 Jet Propulsion Laboratory2 University of Colorado at BoulderContact: paul.d.hamer@jpl.nasa.govUsing a photochemical box model and its adjoint, constructed using the Kinetic Pre-Processor, weinvestigate the impacts of changing satellite observational capacity, observation frequency and quality uponthe ability to both understand and predict the nature of peak ozone events within a variety of pollutedenvironments. The model consists of a chemical mechanism based on the Master Chemical Mechanismutilising 171 chemical species and 524 chemical reactions interacting with emissions, dry deposition andmixing schemes. The model was run under a variety of conditions designed to simulate a range ofsummertime polluted environments spanning a range of NOx and volatile organic compound regimes(VOCs). Using the forward model we were able to generate simulated atmospheric conditions representativeof a particular polluted environment, which could in turn be used to generate a set of satellite pseudoobservations (with noise) of key photochemical constituents. Next the prediction model was run under aperturbed emission scenario with specified errors in the initial guess of the emissions scaling factors. Theprediction model was then forced back to the truth using variational data assimilation and the pseudoobservations. Using this described method we assess the optimal time of observation and the diversity ofobserved chemical species required to provide acceptable forecast estimates of ozone concentrations.Different observing strategies become favourable as the photochemical regime changes according to NOxand VOC concentrations. For instance, under VOC limited photochemical regimes in the presence of modelVOC emission uncertainties, observations of CO and NO2 from space borne platforms are insufficient toconstrain emission uncertainties and allow successful ozone prediction. In such cases, the residual errors forozone can be up to 20 ppbv in scenarios that are sensitive to VOC emissions.P-Observations 1.32 ID:4233 15:35Source contributions to carbon monoxide, black carbon and ozone distributions in the ArcticLouisa Emmons, Simone Tilmes, Gabriele Pfister, Jean-Francois Lamarque, David EdwardsNational Center for Atmospheric ResearchContact: emmons@ucar.eduThe Arctic troposphere is heavily polluted in Winter and Spring as a result of long-range transport fromnorthern mid-latitude continents and the lack of photochemical activity needed to cleanse the atmosphere.Massive forest fires in boreal Eurasia and North America impact the Arctic in the Spring and Summer. Thistalk will integrate fine resolution aircraft campaign measurements with global-scale satellite observationsand global chemistry model simulations to examine the sources and impacts of pollution in the Arctic.Aircraft measurements from the NASA ARCTAS, NOAA ARCPAC, POLARCAT and NSF/NCARiCACGP-IGAC 2010 12 July, 2010