J. Woo

Konkuk University, Sŏul, Seoul, South Korea

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Publications (39)14.43 Total impact

  • H. Kim, J. Woo, T. Jung, Y. Eo
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    ABSTRACT: Over several decades, increasing NOx emissions in the East Asia region have been featured on a number of articles due to their significant contributions to the regional ozone formation and the global NOx emissions budget. However, it is believed that the bottom-up emission inventories of NOx for East Asia are quite uncertain and need to be improved. Although several inversion-based quantitative comparison studies (i.e. top-down versus bottom-up emissions) have been conducted to investigate the reliability of the current NOx emission inventories, uncertainties induced by satellite retrieval and chemical transport modeling data on the inter-comparison between bottom-up and top-down emissions have not been well addressed to our knowledge. In this research, we evaluate our NO2 modeling emissions inventory for East Asia using the satellite-based top-down NO2 emission estimation method for April and October 2008. For the top-down estimation, we investigated an optimal combination of NO2 column datasets from multiple satellite sensors (i.e., the GOME2 on ESA's MetOp, SCIAMACHY on ESA's Envisat, and the OMI on NASA's Aura) and the CMAQ-CCTM runs. Furthermore, we address the uncertainties arise in the process of the top-down NO2 emission estimation. We will present our evaluation results for the East-Asian bottom-up NO2 emissions with respect to the uncertainties of satellite-based top-down emission estimates.
    AGU Fall Meeting Abstracts. 12/2011;
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    ABSTRACT: A scanning UV-Visible Spectrometer, GEMS (Geostationary Environment Spectrometer) is planned to be launched in 2018 onboard a geostationary satellite, GeoKOMPSAT(Geostationary Korea Multi-Purpose SATellite by KARI(Korea Aerospace Research Institute), together with ABI(Advanced Baseline Imager) and GOCI-2 (Geostationary Ocean Color Imager). Synchronous measurements of air pollutants together with the meteorological variables and ocean color information are expected to contribute to better scientific understanding on the distribution and transboundary transportation of air pollution, and on interactions between meteorology and air chemistry in the Asia-Pacific region. This mission is expected to improve the accuracy of air quality forecasting and reduce current discrepancy between the model and observation. Furthermore, constellation of the GeoKOMPSAT with Senteniel-4 in Europe and GEOCAPE in America in 2017-2020 time frame can result in great synergistic outcomes including enhancing significantly our understanding in globalization of tropospheric pollution.
    AGU Fall Meeting Abstracts. 12/2011;
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    ABSTRACT: The Arctic Research of the Composition of the Troposphere from Aircraft and Satellite (ARCTAS) field mission was conducted in April and June-July 2008 to understand changes in atmospheric composition and climate within the Arctic. Large-scale surveys were conducted by the NASA DC-8 research aircraft instrumented with a detailed chemical payload to investigate pollution within the region resulting from the long-range transport of anthropogenic emissions and widespread biomass burning activity. In-situ CO2 measurements were made using a modified infrared CO2 gas analyzer having a precision of 0.1 ppm and accuracy of +/- 0.25 ppm traceable to the WMO CO2 mole fraction scale, and CO measurements were made by the Differential Absorption CO Measurement (DACOM) instrument with < 1 ppbv or 1 % precision. This analysis focuses on biomass burning plumes detected at different altitudes (0.5 - 12 km) during the spring and summer phases of ARCTAS. We used the slope from an orthogonal distance regression to examine CO2:CO enhancement ratio in both fresh and aged plumes. Aged plumes sampled in the spring had an average CO2:CO slope of 50 (ppm/ppm), and typically contained a mixture of pollution from Asian and European sources with Siberian fire emissions. Fresh emissions sampled over wildfires within North American boreal forests during the summer phase yielded a slope of 9 (ppm/ppm). In this presentation, we will explore other chemical tracers associated with these plumes and trajectory analysis to identify source regions and plume characteristics, as well as compare these results with those from the 2008 ARCPAC (Aerosol, Radiation, and Cloud Processes affecting Arctic Climate) field campaign.
    AGU Fall Meeting Abstracts. 12/2010;
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    ABSTRACT: As a major precursor during the summer season, biogenic species are of primary importance in the ozone and SOAs (secondary organic aerosols) formations. Isoprene and mono-terpene also influence the level of inorganic aerosols (i.e. sulfate and nitrate) by controlling OH radicals. However, biogenic emission fluxes are highly uncertain in East Asia. While isoprene emission fluxes from the GEIA (Global Emissions Inventory Activity) and POET (Precursors of Ozone and their Effects in the Troposphere) inventories estimate approximately 20 Tg yr-1 in East Asia, those from the MEGAN (Model of Emissions of Gases and Aerosols from Nature) and MOHYCAN (MOdel for Hydrocarbon emissions by the CANopy) estimate approximately 10 Tg yr-1 and 5 Tg yr-1, respectively. In order to evaluate and/or quantify the magnitude of biogenic emission fluxes over East Asia, the tropospheric HCHO columns obtained from the GOME (Global Ozone Monitoring Experiment) observations were compared with the HCHO columns from the CMAQ (Community Multi-scale Air Quality) simulations over East Asia. In this study, US EPA Models-3/CMAQ v4.5.1 model simulation using the ACE-ASIA (Asia Pacific Regional Aerosol Characterization Experiment) emission inventory for anthropogenic pollutants and GEIA, POET, MEGAN, and MOHYCAN emission inventories for biogenic species was carried out in conjunction with the Meteorological fields generated from the PSU/NCAR MM5 (Pennsylvania state University/National Center for Atmospheric Research Meso-scale Model 5) model for the summer episodes of the year 2002. In addition to an evaluation of the biogenic emission flux, we investigated the impact of the uncertainty in biogenic emission inventory on inorganic aerosol formations and variations of oxidants (OH, O3, and H2O2) in East Asia. In this study, when the GEIA and POET emission inventories are used, the CMAQ-derived HCHO columns are highly overestimated over East Asia, particularly South China compared with GOME-derived HCHO columns. The CMAQ-derived HCHO columns using the MOHYCAN emission inventory have similar values with the GOME-derived HCHO columns over East Asia. Also, differences in biogenic emission fluxes lead to changes in the levels of nitrates by changing the OH radical concentrations.
    AGU Fall Meeting Abstracts. 12/2010;
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    ABSTRACT: Linear dichroism in metamaterial-twisted nematics structure of nano meta surface is controlled via photoisomerization process. Azo twisted nematic cell structure enables the switching on-off of meta-induced resonance by trans-cis-trans isomerization when irradiated by UV light.
    05/2010;
  • Journal of Biological Chemistry - J BIOL CHEM. 01/2010; 285(18):13966-13978.
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    ABSTRACT: In this study, NO2 columns from the US EPA Models-3/CMAQ model simulations carried out using the 2001 ACE-ASIA (Asia Pacific Regional Aerosol Characterization Experiment) emission inventory over East Asia were compared with the GOME-derived NO2 columns. There were large discrepancies between the CMAQ-predicted and GOME-derived NO2 columns in the fall and winter seasons. In particular, while the CMAQ-predicted NO2 columns produced larger values than the GOME-derived NO2 columns over South Korea for all four seasons, the CMAQ-predicted NO2 columns produced smaller values than the GOME-derived NO2 columns over North China for all seasons with the exception of summer (summer anomaly). It is believed that there might be some error in the NOx emission estimates as well as uncertainty in the NOx chemical loss rates over North China and South Korea. Regarding the latter, this study further focused on the biogenic VOC (BVOC) emissions that were strongly coupled with NOx chemistry during summer in East Asia. This study also investigated whether the CMAQ-modeled NO2/NOx ratios with the possibly overestimated isoprene emissions were higher than those with reduced isoprene emissions. Although changes in both the NOx chemical loss rates and NO2/NOx ratios from CMAQ-modeling with the different isoprene emissions affected the CMAQ-modeled NO2 levels, the effects were found to be limited, mainly due to the low absolute levels of NO2 in summer. Seasonal variations of the NOx emission fluxes over East Asia were further investigated by a set of sensitivity runs of the CMAQ model. Although the results still exhibited the summer anomaly possibly due to the uncertainties in both NOx-related chemistry in the CMAQ model and the GOME measurements, it is believed that consideration of both the seasonal variations in NOx emissions and the correct BVOC emissions in East Asia are critical. Overall, it is estimated that the NOx emissions are underestimated by ~57.3% in North China and overestimated by ~46.1% in South Korea over an entire year. In order to confirm the uncertainty in NOx emissions, the NOx emissions over South Korea and China were further investigated using the ACE-ASIA, REAS (Regional Emission inventory in ASia), and CAPSS (Clean Air Policy Support System) emission inventories. The comparison between the CMAQ-calculated and GOME-derived NO2 columns indicated that both the ACE-ASIA and REAS inventories have some uncertainty in NOx emissions over North China and South Korea, which can also lead to some errors in modeling the formation of ozone and secondary aerosols in South Korea and North China.
    AGU Fall Meeting Abstracts. 12/2009;
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    ABSTRACT: Intercontinental Chemical Transport Experiment (INTEX)-B was an airborne campaign conducted during a 10-week period from March 1 to May 15 in 2006 to understand the transport and transformation of gases and aerosols on transcontinental/intercontinental scales and assess their impact on air quality and climate. In April and July of 2008, NASA also sponsored the Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS) mission that coincided with other International Polar Year (IPY) activities seeking to better understand the behavior of Polar Regions and their roles in the broader Earth System. High-resolution chemical measurements made onboard the NASA DC-8 aircraft during INTEX-B and ARCTAS offer the opportunity to broaden our understanding of the atmospheric behavior of chemicals for Arctic and mid-latitude regions. An emissions inventory and processing methodology have been developed to elucidate the influence of Asian emissions outflow. Remote Sensing-based land cover and atmosphere information has also been included to analyze the effect of plants uptake and emissions. The results of our combined data analysis will be presented at the conference.
    AGU Fall Meeting Abstracts. 12/2009;
  • J. Woo, H. Kim, Y. Eo
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    ABSTRACT: Biogenic Volatile organic compounds (BVOCs) and other air pollutants are play an important role in atmospheric chemistry, such as ozone and aerosol formation. Although many research groups have been focusing on BVOCs in the context of their reactivity related to high ozone and aerosol forming potential, their emissions were poorly quantified. Air quality predictions for those pollutants, therefore, include high uncertainty, especially in the regional scale modeling studies in Asia. Meanwhile, Guenther et al. (2006) developed global scale annual emissions inventory applying MEGAN (Model of Emissions of Gases and Aerosols from Nature) for global atmospheric chemistry models. However, the global scale inventory may not appropriate for the regional study domain. Development of regional-based biogenic emissions inventories, therefore, should be valuable to improve our understanding of regional air quality. In the current study, we estimated BVOC and other pollutants emission from the Asia region using MEGAN model. The modeling framework applied as follows; 1) domain extent : entire Asia, 2) grid resolution : 45km*45km, 3) period and temporal resolution : Spring of 2001, daily 4), landcover : MODIS land data(daily), 5) LAI : MODIS LAI product, 6) Meteorological data : MM5. The amount and temporal/spatial distribution of emissions, and their impact on Asian atmosphere will be discussed. References: - Guenther, A., T. Karl, P. Harley, C. Wiedinmyer, P. Palmer, and C. Geron (2006), Estimates of global terrestrial isoprene emissions using MEGAN (Model of Emissions of Gases and Aerosols from Nature), Atmos. Chem. Phys., 6, 3181-3210.
    AGU Fall Meeting Abstracts. 12/2009;
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    ABSTRACT: To date, atmospheric chemistry measurements have been carried out by many satellite programs to monitor air quality including O3, NO2, SO2, HCHO, CO including OMI, GOME, SCHIAMACHY, MOPITT, and TES. These measurements have provided extensive dataset to monitor daily to annual changes of pollutant distributions, but are lack of capability in detecting the diurnal variation of pollutant’s concentration thus in providing constraints on their sources. Asia, where both anthropogenic and natural sources of pollutants dominate throughout the year, is an important region to understand tropospheric air pollution in global scale. A scanning UV-Visible Spectrometer, named GEMS (Geostationary Environment Spectrometer) is being planned to be launched in 2017-2018 onboard a geostationary satellite, MP-GEOSAT by KARI(Korea Aerospace Research Institute), together with ABI(Advanced Baseline Imager) and GOCI-2 (Geostationary Ocean Color Imager). Synchronous measurements of air pollutants together with the meteorological variables and ocean color information are expected to contribute to better scientific understanding on the distribution and transboundary transportation of air pollution, and on interactions between meteorology and air chemistry in the Asia-Pacific region. This mission is expected to improve the accuracy of air quality forecasting and reduce current discrepancy between the model and observation. Furthermore, constellation of the MP-GEOSAT with GEOCAPE in America and Sentennial-4 in Europe starting in 2017- 2018 time frame can result in great synergistic outcomes including enhancing significantly our understanding in globalization of tropospheric pollution.
    AGU Fall Meeting Abstracts. 11/2009; -1:01.
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    ABSTRACT: Regional-scale observations of atmospheric CO2 and radiocarbon were made over the Canadian Arctic and vicinity during the ARCTAS (Arctic Research of the Composition of the Troposphere from Aircraft and Satellites) mission, part of the wider International Polar Year effort. Large-scale surveys were conducted by the NASA DC-8 research aircraft in 2008 to primarily examine anthropogenic pollution including arctic haze in the spring, and boreal forest fire emissions in the summer. High-resolution in-situ CO2 measurements were made onboard the DC-8 using a modified non-dispersive infrared gas analyzer having a precision of 0.1 ppm and an accuracy of ±0.25 ppm traceable to the WMO CO2 mole fraction scale. The 14C content of CO2 was determined from air remaining in a select subset of whole air canister samples collected and later analyzed at the W. M. Keck Carbon Isotope AMS Facility. These observations provide unique and definitive data sets via their intermediate-scale coverage and frequent vertical profiles (0.1 - 12 km) for examining the variability CO2 exhibits above the Earth’s surface, and for quantifying the fossil fuel contribution to the measured overall CO2 signal. In this presentation, the seasonal and spatial CO2 and radiocarbon distributions will be explored and compared to other recent airborne campaigns; and CO2 sources and sinks inferred using multi-satellite remote sensing datasets, additional chemical tracers, and air mass transport histories. A bottom-up anthropogenic CO2 emissions inventory (1° × 1°) and processing methodology, developed in support of ARCTAS to quantify the influence of long-range transport of Asian CO2 emissions on the ARCTAS sampling domain, will also be discussed.
    AGU Fall Meeting Abstracts. 11/2009; -1:0202.
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    ABSTRACT: National Institute of Environmental Research(NIER), Ministry of Environment, Rep. of Korea is planning GEMS (Geostationary Environment Spectrometer) program to be launched in 2017-2018 onboard a geostationary satellite, MP-GEOSAT of KARI(Korea Aerospace Research Institute). GEMS is a scanning UV-Visible Spectrometer to monitor trans-boundary pollution events in Asia-Pacific region, together with ABI(Advanced Baseline Imager) and GOCI-2 (Geostationary Ocean Color Imager). GEMS is to monitor the distribution of tropospheric O3, NO2, SO2, HCHO, and aerosol in Asia, which is very important region to understand the air quality problems in both regional and global scale. Furthermore, it is essential to monitor air pollution with measurements of meteorological variables for better understanding. This mission is expected to improve the monitoring capability of trans-boundary air pollution events and the accuracy of its forecasting through hourly observation from GEO. Constellation of the MP-GEOSAT with GEOCAPE in America and Sentennial-4 in Europe with launch in 2017- 2018 period can results in great synergistic outcomes including enhancing significantly our understanding in globalization of tropospheric pollution.
    AGU Fall Meeting Abstracts. 01/2009;
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    ABSTRACT: Forest fires are one of important sources for carbonaceous aerosols which are mostly comprised of organic carbon (OC) and black carbon (BC) aerosols. They have important climatic implications because of their extinction of solar radiation: OC scatters and BC absorbs solar radiation. These contrasting radiative properties add another complexity to our understanding the effects of those aerosols on climate. In spring 2003, the record-breaking intense forest fires occurred over Siberia, which emitted huge amount of aerosols in the atmosphere. We here examine the effect of these Siberian forest fires aerosols on regional climate in East Asia using a combination of numerical models and observations. First a global chemical transport model (CTM) with a biomass burning emission inventory constrained by satellite was used to simulate the enhancements of the aerosol concentrations due to the Siberian fires over East Asia. Our simulated aerosols were evaluated against the observations from the MODIS satellite and at the EANET sites. We then applied the simulated aerosols concentrations to climate simulations using the National Center for Atmospheric Research (NCAR) coupled global climate model, Community Climate System Model version 3.0 (CCSM3) to examine the impact of Siberian fire aerosols on regional climate. The difference in the model between with and without simulated Siberian fire aerosols defines the impact of fires on regional climate. The results indicated that fire aerosols resulted in a strong cooling at the surface and a general warming in the free troposphere and thus increased atmospheric stability. We also found significant decreases in geopotential heights over Siberia and decreases in cloud cover and precipitation in both Japan and the western North Pacific due to fire aerosols. Such changes were consistent with the observations based on the NCEP/DOE reanalysis II data, indicating the importance of fire impacts for regional climate simulations.
    AGU Fall Meeting Abstracts. 12/2008;
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    ABSTRACT: The Tropical Composition, Clouds, and Climate, Coupling experiment (TC4) was an airborne campaign conducted during July and August in 2007 to investigate the structures, properties, and processes of the upper troposphere within the tropics. In April and July of 2008, NASA also sponsored the Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS) mission that coincided with other International Polar Year (IPY) activities seeking to better understand the behavior of Polar Regions and their roles in the broader Earth System. High-resolution carbon dioxide measurements made onboard the NASA DC-8 aircraft during TC4 and ARCTAS offer the opportunity to broaden our understanding of the atmospheric behavior of carbon dioxide (CO2) for Arctic and Tropical regions. An emissions inventory and processing methodology have been developed to elucidate the influence of emissions on the regional atmospheric CO2 concentration. Remote Sensing-based land cover information has also been included to analyze the effect of plant uptake and respiration. The results of our combined data analysis will be presented at the conference.
    AGU Fall Meeting Abstracts. 12/2008;
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    ABSTRACT: The structure of a city is complex due to the construction of high-rise buildings and extensive road networks. Complex structure of a highly urbanized city causes many different dispersion patterns of wind and pollutants. The importance of micro-scale air quality management, therefore, is getting larger. Micro-scale air pollution lasts only for minutes to hours and occurs near to our living environment. Because of its short lifetime and small spatial extent, our understanding for micro-scale air quality has been pretty limited. In the micro-scale air pollution, describing 3-dimensional air flow, which incorporates detail building structures and terrain, is very important to see the realistic pollutant dispersion. In addition, there are many cases that the air pollution in an urbanized city is affected directly by strong local emission events. Detailed emission inventory from various emission events in urban area, therefore, should be developed. We try to establish D GIS database in an urban area and develop a micro-scale emission inventory. The GIS database and emission inventory can be used and applied to micro-scale atmospheric modeling in the Konkuk University Complex, Seoul, Korea. Methodologies and initial results of establishing D GIS database and detailed emission inventory will be presented. Acknowledgement This research was supported by a grant from Seoul R&BD Program (GS070167)
    AGU Fall Meeting Abstracts. 12/2008;
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    ABSTRACT: Emissions of greenhouse gases and their precursors have been identified as significant driving forces of global changes [IPCC, 1995] that occur on a wide range of spatial and temporal scales and often differ among regions. In order to correctly understand the impact of global climate change on regional air quality, it is required to prepare the most up-to-date global emissions inventory. The major goal of this research is to review the current emission inventories and to select the most appropriate ones for the global chemistry-climate modeling project of Korean Ministry of Environment. We have researched several inventory works such as EDGAR, GEIA, RETRO, GFED, for forecasting and hindcasting as well. The evaluation is based on data availability and accessibility, spatial-temporal coverage, resolution, and so on. In our study, we will present the characteristics of reviewed emission inventories and a resulting emissions inventory. Acknowledgement This research was performed under the support of "National Comprehensive Measures against Climate Change" Program by Ministry of Environment, Korea (Grant No. 1700-1737-322-210-13).
    AGU Fall Meeting Abstracts. 12/2008;
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    ABSTRACT: This study examined the estimation accuracy of NOx emissions over East Asia with particular focus on North China and South Korea due to their strong source (North China)-receptor (South Korea) relationship. In order to determine contributions of North China emissions to South Korean air quality accurately, it is important to examine the accuracy of the emission inventories of both regions. In this study, NO2 columns from the Models-3/CMAQ model simulations carried out using the 2001 ACE-ASIA emission inventory over East Asia were compared with the GOME-derived NO2 columns. There were large discrepancies between the CMAQ-predicted and GOME-derived NO2 columns in the fall and winter seasons. In particular, while the CMAQ-predicted NO2 columns produced larger values than the GOME- derived NO2 columns over South Korea for all four seasons, the CMAQ-predicted NO2 columns produced smaller values than the GOME-derived NO2 columns over North China for all seasons with the exception of summer. It is believed that there might be some estimation error in the NOx emissions as well as large uncertainty in NOx loss rates over North China and South Korea.Regarding the latter, this study further focused on the biogenic VOC emissions that were strongly coupled with NOx chemistry in East Asia. It was found that the rates of NOx loss determined by CMAQ modeling studies might be significantly low due to the possible overestimation of biogenic isoprene emissions during summer, particularly in China. A comparison between the CMAQ-predicted and GOME-derived NO2 columns indicated that the ACE-ASIA inventory has some uncertainties in NOx emissions over North China and South Korea, which can lead to some error in modeling the formation of ozone and secondary aerosols in South Korea and North China.
    Atmospheric Chemistry and Physics 01/2008; 8(5):17297-17341. · 4.88 Impact Factor
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    ABSTRACT: Atmospheric CO2 inversion studies infer surface sources and sinks from observations and models. These studies usually require determination of the fossil fuel component of the observation, which can be estimated using anthropogenic tracers such as CO. The objective of this study is to demonstrate a new CO tracer method that accounts for overlapping forest fire and photochemical CO influences, and to quantify several aspects of the uncertainty in the CO tracer technique. Photochemistry model results and observations from the International Consortium for Atmospheric Research on Transport and Transformation experiment are used to quantify changes in the fossil fuel CO2 prediction from the CO tracer method with and without the inclusion of CO from biomass burning and photochemistry. Although the chemical sources and sinks tend to offset each other, there are regions where the chemical reactions change fossil fuel CO2 predictions by up to ±4 ppm. Including biomass burning lowers fossil fuel CO2 by an average of 12 ppm in plumes heavily influenced by long-range transport of forest fire CO. An alternate fossil fuel CO2 calculation is done in a power plant plume using SO2 as a tracer, giving a change in 20 ppm from the CO method, indicative of uncertainty in the assumed CO:CO2 ratio.
    Tellus B 03/2007; 59(2):199 - 210. · 3.20 Impact Factor
  • J. Woo, Y. Choi, S. A. Vay
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    ABSTRACT: The Intercontinental Chemical Transport Experiment (INTEX-NA) is a major NASA science campaign envisioned to understand the transport and transformation of gases and aerosols on transcontinental and intercontinental scales and their impact on air quality and climate. During the campaign series, high temporal resolution (1 Hz) in situ CO2 data were recorded aboard the NASA DC-8 aircraft over sparsely sampled areas of North America and adjacent ocean basins. When coupled with other simultaneous tracer measurements on the DC-8, the in situ CO2 observations provide valuable regional-scale information on carbon sources and sinks. In contrast to the INTEX-NA airborne observations, supporting meteorological data and available modeling tools, the bottom-up U.S. CO2 emissions inventory is not at the same level of sophistication. This is mainly because the traditional focus of monitoring atmospheric CO2 behavior has been directed towards global warming research at both national and international scales rather than at the regional level. To fill the gap between these data scales and improve our understating on fine-scale carbon behavior, we developed a bottom-up modeling inventory in support of INTEX-NA. The Inventory Data Analyzer (IDA) format, which has been widely used for the U.S. EPA's modeling version of the National Emissions Inventory (NEI), was selected as our inventory format so that we can use the emissions processing and air quality modeling tools developed for various scientific and regulatory applications. As a first step, a state-level CO2 emissions inventory was developed using the U.S. EPA's State Tool for Estimating Greenhouse Gas Emissions (i.e. State Inventory Tool, or SIT). We then allocate a state level, database format inventory into a county/point level, IDA format inventory. Subsequently, the Sparse Matrix Operator Kernel Emissions (SMOKE) emissions modeling/processing system was used to create a higher resolution, gridded emissions inventory that can be directly assimilated by chemical transport models. We also utilize data from the EPA's Continuous Emissions Monitoring System (CEMS) to improve the spatial resolution of the emissions data for major point sources. The bottom-up emissions inventory at higher resolution can be beneficial to a variety of related research areas e.g. chemical transport modeling, inverse (or backward) quantification of emissions using ground, airborne, or satellite measurements. The bottom-up inventory development procedure, modeling inventory conversion, emissions processing, and modeling and data analysis results will be presented and discussed.
    AGU Fall Meeting Abstracts. 12/2006;
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    ABSTRACT: North American terrestrial ecosystems are major sources and sinks of carbon. Precise measurement of atmospheric CO2 concentrations plays an important role in the development and testing of carbon cycle models quantifying the influence of terrestrial CO2 exchange on the North American carbon budget. During the summer 2004 Intercontinental Chemical Transport Experiment North America (INTEX-NA) campaign, regional scale in-situ measurements of atmospheric CO2 were made from the NASA DC-8 affording the opportunity to explore how land surface heterogeneity relates to the airborne observations utilizing remote-sensing data products and GIS-based methods. These 1 Hz data reveal the seasonal biospheric uptake of CO2 over portions of the U.S. continent, especially east of 90°W below 2 km, compared to higher mixing ratios over water as well as within the upper troposphere where well-mixed, aged air masses were sampled. In this study, we use several remote sensing derived biophysical parameters from the LANDSAT, NOAA AVHRR, and MODIS sensors to specify spatiotemporal patterns of land use cover and vegetation characteristics for linking the airborne measurements of CO2 data with terrestrial sources of carbon. Also, CO2 flux footprint outputs from a 3-D Lagrangian atmospheric model have been integrated with satellite remote sensing data to infer CO2 variations across heterogeneous landscapes. In examining the landscape mosaic utilizing these available tools, preliminary results suggest that the lowest CO2 mixing ratios observed during INTEX-NA were over agricultural fields in Illinois dominated by corn then secondarily soybean crops. Low CO2 concentrations are attributable to sampling during the peak growing season over such C4 plants as corn having a higher photosynthetic rate via the C4-dicarboxylic acid pathway of carbon fixation compared to C3 plants such as soybeans. In addition to LANDSAT derived land cover data, results from comparisons of the airborne CO2 observations with vegetation indices of NDVI and EVI derived from MODIS data were used. Higher CO2 mixing ratios anti-correlated with the vegetation indices derived from MODIS data were observed. This is attributable to the photosynthetic uptake of CO2 by plants and convective mixing of the atmosphere. Details of satellite data characteristics related with the in-situ CO2 measurements will be presented.
    AGU Fall Meeting Abstracts. 12/2006;