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List of Abstracts 116Lightning is responsible for an estimated 15 percent of total global NOx emissions, but is one of the mostprominent sources in the upper troposphere over the United States in summer. In this study, we presentevidence of lightning-generated NO2 (LNO2) using data from the Ozone Monitoring Instrument (OMI) onthe Aura satellite for several case studies over the Central US, Gulf of Mexico, and Western Atlantic. Thesecases of LNO2 enhancement have been identified through examination of the OMI NO2 products and ofFLEXPART lightning-generated NOx (LNOx) model output. Mean OMI NO2 columns from a set of dayswith little or no lightning in and downwind of the regions of interest are subtracted from the daily data toobtain the presumed LNO2 signal. Model estimates of LNO2 profiles from previous studies in anddownwind of convective storms are employed in air mass factor calculations to convert the OMI NO2 slantcolumns into vertical column amounts. We employ improved off-line processing techniques developed instudies of tropical convective systems to minimize known artifacts in the OMI data. The LNO2 amountsfrom OMI are converted to LNOx amounts using NASA Global Modeling Initiative (GMI) calculations of[NOx]/[NO2] ratios. Back trajectories at middle and upper tropospheric levels are used to obtain numbers ofcloud-to-ground (CG) lightning flashes observed by the National Lightning Detection Network (NLDN).These flash counts are combined with estimates of the climatological IC/CG ratios to obtain the total numberof lightning flashes associated with the observed LNOx enhancements. A vertically-weighted averagenumber of upwind flashes was obtained using a typical profile of LNOx mass from a series of midlatitudecloud-resolved storm chemistry simulations. Combining the LNOx results and upwind flash counts, weobtain the production of LNOx per lightning flash in these mid-latitude storms. We compare our results toprevious studies of other mid-latitude storms and to studies of tropical and sub-tropical systems. Resultsyield values in the range obtained for midlatitude storms through other estimation techniques (e.g., aircraftmeasurements, cloud-resolved models).Sources 2.2 ID:4550 15:45Quantification of fossil fuel CO 2 emissions from East Asia using atmospheric observations of ∆ 14 CO 2Jocelyn Turnbull 1 , Yong Chung 2 , Jay Gregg 3 , Scott Lehman 4 , John Miller 1 , Pieter Tans 11 NOAA/ESRL2 Korea Centre for Atmospheric Environmental Research3 University of Maryland4 University of ColoradoContact: jocelyn.turnbull@noaa.govFossil fuel CO 2 emissions are the largest net source of CO 2 to the atmosphere, and accurate quantification ofthese emissions is essential to furthering our understanding of the global carbon cycle. Currently, fossil fuelCO 2 (CO 2 ff) emissions are estimated from bottom-up inventories of fossil fuel use reported by governmentsand industry. Measurements of the radioactive isotope 14 C in CO 2 provide an independent, objective methodof constraining CO 2 ff emissions, since fossil fuel derived CO 2 , unlike other CO 2 sources, is devoid of 14 C.These measurements can be used to evaluate bottom-up inventories of CO 2 ff, and, using a multi-speciesapproach, also constrain emissions of other trace gases. Emissions from East Asia are of particular interest,since they contribute ~25% of global total CO 2 ff emissions, and are growing rapidly by 8-10% per year, butare quite uncertain compared to other regions. We quantitatively determine recently added CO 2 ff in samplesfrom the NOAA/ESRL cooperative sampling network site at Tae-Ahn Peninsula, Republic of Korea, whichusually sees air which has recently passed over northeastern China and Korea. Samples typically contain afew ppm of CO 2 ff from China, and Korea contributes additional CO 2 ff in some samples. The observed CO 2also shows large variability due to biospheric CO 2 exchange, even in winter, so that CO 2 measurements alonecannot accurately estimate CO 2 ff. We compare the observational results with estimates of CO 2 ff from aLagrangian particle dispersion model and a prior estimate of CO 2 ff emissions, examining our ability toevaluate the reported emissions and determine quantitative uncertainties to these emissions. MeasurementsiCACGP-IGAC 2010 13 July, 2010