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Sample records for acp09 hodzic acp09

  1. Simultaneous physical retrieval of atmospheric and surface state from Martian spectra: the phi MARS algorithm and application to TES

    NASA Astrophysics Data System (ADS)

    Liuzzi, G.; Masiello, G.; Serio, C.; Mancarella, F.; Fonti, S.; Roush, T.

    The problem of fully simultaneous retrieval of surface and atmosphere has been satisfactorily addressed as far as Earth is concerned in many works \\citep{masACP09,carENSO05}, especially for high-resolution instruments. However, such retrieval know-how has been not completely implemented in other planetary contexts. In this perspective, we present a new methodology for the simultaneous retrieval of surface and atmospheric parameters of Mars. The methodology, fully explained in \\cite{liuzzi2015} is based on a non-linear, iterative optimal estimation scheme, supported by a statistical retrieval procedure used to initialize the physical retrieval algorithm with a reliable first guess of the atmospheric parameters. The forward module \\cite{liuzzi2014} is fully integrated with the inverse one, and it is a monochromatic radiative transfer model with the capability to calculate genuine analytical Jacobians of any desired geophysical parameter. We describe both the mathematical framework of the methodology and, as a proof of concept, its application to a large sample of data acquired by the Thermal Emission Spectrometer (TES). Results are drawn for the case of surface temperature and emissivity, atmospheric temperature profile, water vapour, dust and ice mixing ratios. Some work has also been done for revisiting the claims of methane detection with TES data \\citep{fon10,fonti2015}. Comparison with climate models and other TES data analyses show a very good agreement and consistency. Moreover, we will show how the methodology can be applied to other instruments looking at Mars, simply customizing part of the forward and reverse modules.

  2. Improving the simulation of organic aerosols from anthropogenic and burning sources: a simplified SOA formation mechanism and the impact of trash burning

    NASA Astrophysics Data System (ADS)

    Hodzic, A.; Wiedinmyer, C.; Jimenez, J. L.

    2011-12-01

    Organic aerosols (OA) are an major component of fine aerosols, but their sources are poorly understood. We present results of two methods to improve OA predictions in anthropogenic pollution and biomass-burning impacted regions. (1) An empirical parameterization for secondary organic aerosol (SOA) formation in polluted air and biomass burning smoke is implemented into community chemistry-transport models (WRF/Chem and CHIMERE) and tested in this work, towards the goal of a computationally inexpensive method to calculate pollution and biomass burning SOA. This approach is based on the observed proportionality of SOA concentrations to excess CO and photochemical age of the airmass, as described in Hodzic and Jimenez (GMDD, 2011). The oxygen to carbon ratio in organic aerosols is also parameterizated vs. photochemical aged based on the ambient observations, and is used to estimate the aerosol hygroscopicity and CCN activity. The predicted SOA is assessed against observations from the Mexico City metropolitan area during the MILAGRO 2006 field experiment, and compared to previous model results using the more complex volatility basis approach (VBS) of Robinson et al.. The results suggest that the simplified approach reproduces the observed average SOA mass within 30% in the urban area and downwind, and gives better results than the original VBS. In addition to being much less computationally expensive than VBS-type methods, the empirical approach can also be used in regions where the emissions of SOA precursors are not yet available. (2) The contribution of trash burning emissions to primary and secondary organic aerosols in Mexico City are estimated, using a recently-developed emission inventory. Submicron antimony (Sb) is used as a garbage-burning tracer following the results of Christian et al. (ACP 2010), which allows evaluation of the emissions inventory. Results suggests that trash burning may be an appreciable source of organic aerosols in the Mexico City

  3. Development of new parameterizations for SOA production from SVOC and IVOC oxidation

    NASA Astrophysics Data System (ADS)

    Lemaire, Vincent; Coll, Isabelle; Camredon, Marie; Aumont, Bernard; Siour, Guillaume

    2014-05-01

    Recent experimental studies have demonstrated the partially volatile pattern of primary organic aerosol (POA) that is actually associated with organic species of so-called intermediate volatility (IVOCs), and by semi-volatile (SVOCs) species. Indeed, 50% to 75% of the total emitted mass of POA may be present in the atmospheric gas phase in accordance with the thermodynamic properties of its components (Shrivastava et al., 2006). During the processing of the emission plume, this gaseous material will then undergo photochemical oxidation, enhancing the production of secondary organic aerosol (SOA) (Robinson et al., 2007; Hodzic et al., 2010; Lee-Taylor et al., 2011). Considering POA as non volatile in Chemistry Transport Models (CTMs) could thus lead to an underestimation of SOA and an overestimation of POA (Aksoyoglu et al., 2011) and bias the temporal formation of the organic aerosol (Kroll et al., 2007; Presto et al., 2012). However, very rare experimental data exist on the fate of these species and their aerosol yield, but all existing studies have shown a significant SOA production (Presto et al., 2009; Miracolo et al., 2010; Lambe et al., 2012). Our works aims at including and testing in the CHIMERE CTM new parameterizations of SOA formation from the oxidation of IVOCs and SVOCs, arising from explicit 0D-model experiments. Our approach is based on the works of Aumont et al., (2013) who used the GECKO-A tool (Generator for Explicit Chemistry and Kinetics of Organics in the Atmosphere) to generate the explicit chemistry and gas-particle partitioning of superior alkanes and their oxidation products. Using this explicit scheme, Aumont et al., (2013) indeed produced 0D simulations of the oxidation of given SVOCs and IVOCs under different initial conditions of organic aerosol mass. We first focused on the chemistry of n-hexadecane. From the 0D-experiments, we tested the influence of the number of first generation surrogate species and the number of generation taken

  4. Po-Basin Atmospheric Composition during the Pegasos Field Campaign (summer 2012): Evaluation of ninfa/aodeM Simulation with In-Situ e Remote Sensing Observations

    NASA Astrophysics Data System (ADS)

    Landi, Tony C.; Bonafe, Giovanni; Stortini, Michele; Minguzzi, Enrico; Cristofanelli, Paolo; Marinoni, Angela; Giulianelli, Lara; Sandrini, Silvia; Gilardoni, Stefania; Rinaldi, Matteo; Ricciardelli, Isabella

    2014-05-01

    Within the EU project PEGASOS one of three field campaigns took place in the Po Valley during the summer of 2012. Photochemistry, particle formation, and particle properties related to diurnal evolution of the PBL were investigated through both in-situ and airborne measurements on board a Zeppelin NT air ship. In addition, 3-D air quality modeling systems were implemented over the Po valley for the summer 2012 to better characterize the atmospheric conditions, in terms of meteorological parameters and chemical composition. In this work, we present a comparison between atmospheric composition simulations carried out by the modeling system NINFA/AODEM with measurements performed during the PEGASOS field campaign for the period 13 June - 12 July 2012. NINFA (Stortini et al., 2007) is based on the chemical transport model CHIMERE (Bessagnet et al., 2008), driven by COSMO-I7, the meteorological Italian Limited Area Model, (Steppeler et al., 2003). Boundary conditions are provided by Prev'air data (www.prevair.org), and emission data input are based on regional, national and European inventory. Besides, a post-processing tool for aerosol optical properties calculation, called AODEM (Landi T. C. 2013) was implemented. Thus, predictions of Aerosol Optical Depth and aerosol extinction coefficient were also used for model comparison to vertical-resolved observations. For this experiment, NINFA/AODEM has been also evaluated by using measurements of size-segregated aerosol samples, number particles concentration and aerosol optical properties collected on hourly basis at the 3 different sampling sites representative of urban background (Bologna), rural background (San Pietro Capofiume) and remote high altitude station (Monte Cimone 2165 ma.s.l.). ). In addition, we focused on new particles formations events and long range transports from Northern Africa observed during the field campaign. References Bessagnet, Bertrand, Laurent Menut, Gabriele Curci, Alma Hodzic, Bruno

  5. Potential contribution of semi-volatile and intermediate volatility primary organic compounds to secondary organic aerosol in the Mexico City region

    NASA Astrophysics Data System (ADS)

    Hodzic, A.; Jimenez, J. L.; Madronich, S.; Canagaratna, M. R.; Decarlo, P. F.; Kleinman, L.; Fast, J.

    2010-01-01

    It has been established that observed local and regional levels of secondary organic aerosols (SOA) in polluted areas cannot be explained by the oxidation and partitioning of anthropogenic and biogenic VOC precursors, at least using current mechanisms and parameterizations. In this study, the 3-D regional air quality model CHIMERE is applied to quantify the contribution to SOA formation of recently identified semi-volatile and intermediate volatility organic vapors (S/IVOC) in and around Mexico City for the MILAGRO field experiment during March 2006. The model has been updated to include explicitly the volatility distribution of primary organic aerosols (POA), their gas-particle partitioning and the gas-phase oxidation of the vapors. Two recently proposed parameterizations, those of Robinson et al. (2007) ("ROB") and Grieshop et al. (2009) ("GRI") are compared and evaluated against surface and aircraft measurements. The 3-D model results are assessed by comparing with the concentrations of OA components from Positive Matrix Factorization of Aerosol Mass Spectrometer (AMS) data, and for the first time also with oxygen-to-carbon ratios derived from high-resolution AMS measurements. The results show a substantial enhancement in predicted SOA concentrations (3-6 times) with respect to the previously published base case without S/IVOCs (Hodzic et al., 2009), both within and downwind of the city leading to much reduced discrepancies with the total OA measurements. The predicted anthropogenic POA levels are found to agree within 20% with the observed HOA concentrations for both the ROB and GRI simulations, consistent with the interpretation of the emissions inventory by previous studies. The impact of biomass burning POA within the city is underestimated in comparison to the AMS BBOA, presumably due to insufficient nighttime smoldering emissions. Model improvements in OA predictions are associated with the better-captured SOA magnitude and diurnal variability. The

  6. Modeling organic aerosols in a megacity: potential contribution of semi-volatile and intermediate volatility primary organic compounds to secondary organic aerosol formation

    NASA Astrophysics Data System (ADS)

    Hodzic, A.; Jimenez, J. L.; Madronich, S.; Canagaratna, M. R.; Decarlo, P. F.; Kleinman, L.; Fast, J.

    2010-06-01

    It has been established that observed local and regional levels of secondary organic aerosols (SOA) in polluted areas cannot be explained by the oxidation and partitioning of anthropogenic and biogenic VOC precursors, at least using current mechanisms and parameterizations. In this study, the 3-D regional air quality model CHIMERE is applied to estimate the potential contribution to SOA formation of recently identified semi-volatile and intermediate volatility organic precursors (S/IVOC) in and around Mexico City for the MILAGRO field experiment during March 2006. The model has been updated to include explicitly the volatility distribution of primary organic aerosols (POA), their gas-particle partitioning and the gas-phase oxidation of the vapors. Two recently proposed parameterizations, those of Robinson et al. (2007) ("ROB") and Grieshop et al. (2009) ("GRI") are compared and evaluated against surface and aircraft measurements. The 3-D model results are assessed by comparing with the concentrations of OA components from Positive Matrix Factorization of Aerosol Mass Spectrometer (AMS) data, and for the first time also with oxygen-to-carbon ratios derived from high-resolution AMS measurements. The results show a substantial enhancement in predicted SOA concentrations (2-4 times) with respect to the previously published base case without S/IVOCs (Hodzic et al., 2009), both within and downwind of the city leading to much reduced discrepancies with the total OA measurements. Model improvements in OA predictions are associated with the better-captured SOA magnitude and diurnal variability. The predicted production from anthropogenic and biomass burning S/IVOC represents 40-60% of the total measured SOA at the surface during the day and is somewhat larger than that from commonly measured aromatic VOCs, especially at the T1 site at the edge of the city. The SOA production from the continued multi-generation S/IVOC oxidation products continues actively downwind. Similar

  7. Potential contribution of semi-volatile and intermediate volatility primary organic compounds to secondary organic aerosol in the Mexico City region

    SciTech Connect

    Hodzic, A.; Kleinman, L.; Jimenez, J. L.; Madronich, S.; Canagaratna, M. R.; DeCarlo, P. F.; Fast, J.

    2010-03-01

    It has been established that observed local and regional levels of secondary organic aerosols (SOA) in polluted areas cannot be explained by the oxidation and partitioning of anthropogenic and biogenic VOC precursors, at least using current mechanisms and parameterizations. In this study, the 3-D regional air quality model CHIMERE is applied to quantify the contribution to SOA formation of recently identified semi-volatile and intermediate volatility organic vapors (S/IVOC) in and around Mexico City for the MILAGRO field experiment during March 2006. The model has been updated to include explicitly the volatility distribution of primary organic aerosols (POA), their gas-particle partitioning and the gas-phase oxidation of the vapors. Two recently proposed parameterizations, those of Robinson et al. (2007) ('ROB') and Grieshop et al. (2009) ('GRI') are compared and evaluated against surface and aircraft measurements. The 3-D model results are assessed by comparing with the concentrations of OA components from Positive Matrix Factorization of Aerosol Mass Spectrometer (AMS) data, and for the first time also with oxygen-to-carbon ratios derived from high-resolution AMS measurements. The results show a substantial enhancement in predicted SOA concentrations (3–6 times) with respect to the previously published base case without S/IVOCs (Hodzic et al., 2009), both within and downwind of the city leading to much reduced discrepancies with the total OA measurements. The predicted anthropogenic POA levels are found to agree within 20% with the observed HOA concentrations for both the ROB and GRI simulations, consistent with the interpretation of the emissions inventory by previous studies. The impact of biomass burning POA within the city is underestimated in comparison to the AMS BBOA, presumably due to insufficient nighttime smoldering emissions. Model improvements in OA predictions are associated with the better-captured SOA magnitude and diurnal variability. The

  8. Modeling organic aerosols in a megacity: potential contribution of semi-volatile and intermediate volatility primary organic compounds to secondary organic aerosol formation

    SciTech Connect

    Hodzic, Alma; Jimenez, Jose L.; Madronich, Sasha; Canagaratna, M. R.; DeCarlo, Peter F.; Kleinman, Lawrence I.; Fast, Jerome D.

    2010-06-21

    It has been established that observed local and regional levels of secondary organic aerosols (SOA) in polluted areas cannot be explained by the oxidation and partitioning of traditional anthropogenic and biogenic VOC precursors. In this study, the 3D regional air quality model CHIMERE is applied to quantify the contribution to SOA formation of recently identified semi-volatile and intermediate volatility organic vapors (S/IVOC) in and around Mexico City for the MILAGRO field experiment during March 2006. The model has been updated to explicitly include the volatility distribution of primary organic aerosols (POA), their gas-particle partitioning and the gas-phase oxidation of the vapors. Two recently proposed parameterizations, those of Robinson et al. (2007) ("ROB") and Grieshop et al. (2009) ("GRI") are compared and evaluated against surface and aircraft measurements. For the first time, 3D model results are assessed by comparing with the concentrations of OA components from Positive Matrix Factorization of Aerosol Mass Spectrometer (AMS) data, but also against and oxygen-to-carbon ratios derived from high-resolution AMS measurements. The results show a substantial enhancement in predicted SOA concentrations (3-6 times) with respect to the previously published base case without S/IVOCs (Hodzic et al., 2009), both within and downwind of the city leading to much reduced discrepancies with the total OA measurements. The predicted anthropogenic POA levels are found to agree within 20% with the observed HOA concentrations for both the ROB and GRI simulations, consistent with the interpretation of the emissions inventory by previous studies. The impact of biomass burning POA within the city is underestimated in comparison to the AMS BBOA, presumably due to insufficient nighttime smoldering emissions. Model improvements in OA predictions are associated with the better-captured SOA magnitude and diurnal variability. The production from anthropogenic and biomass burning

  9. Modeling organic aerosols in a megacity: Potential contribution of semi-volatile and intermediate volatility primary organic compounds to secondary organic aerosol formation

    SciTech Connect

    Hodzic, A.; Kleinman, L.; Jimenez, J. L.; Madronich, S.; Canagaratna, M. R.; DeCarlo, P. F.; Fast, J.

    2010-06-01

    It has been established that observed local and regional levels of secondary organic aerosols (SOA) in polluted areas cannot be explained by the oxidation and partitioning of anthropogenic and biogenic VOC precursors, at least using current mechanisms and parameterizations. In this study, the 3-D regional air quality model CHIMERE is applied to estimate the potential contribution to SOA formation of recently identified semi-volatile and intermediate volatility organic precursors (S/IVOC) in and around Mexico City for the MILAGRO field experiment during March 2006. The model has been updated to include explicitly the volatility distribution of primary organic aerosols (POA), their gas-particle partitioning and the gas-phase oxidation of the vapors. Two recently proposed parameterizations, those of Robinson et al. (2007) ('ROB') and Grieshop et al. (2009) ('GRI') are compared and evaluated against surface and aircraft measurements. The 3-D model results are assessed by comparing with the concentrations of OA components from Positive Matrix Factorization of Aerosol Mass Spectrometer (AMS) data, and for the first time also with oxygen-to-carbon ratios derived from high-resolution AMS measurements. The results show a substantial enhancement in predicted SOA concentrations (2-4 times) with respect to the previously published base case without S/IVOCs (Hodzic et al., 2009), both within and downwind of the city leading to much reduced discrepancies with the total OA measurements. Model improvements in OA predictions are associated with the better-captured SOA magnitude and diurnal variability. The predicted production from anthropogenic and biomass burning S/IVOC represents 40-60% of the total measured SOA at the surface during the day and is somewhat larger than that from commonly measured aromatic VOCs, especially at the T1 site at the edge of the city. The SOA production from the continued multi-generation S/IVOC oxidation products continues actively downwind. Similar