Now showing items 21-40 of 293

    • Atmospheric Acetylene and its Relationship with CO as an Indicator of Air Mass Age 

      Xiao, Yaping; Jacob, Daniel J.; Turquety, Solene (American Geophysical Union, 2007)
      Acetylene (C2H2) and CO originating from combustion are strongly correlated in atmospheric observations, offering constraints on atmospheric dilution and chemical aging. We examine here the C2H2-CO relationships in aircraft ...
    • Atmospheric budget of acetone 

      Jacob, Daniel James; Field, Brendan; Jin, Emily; Bey, Isabelle; Li, Qinbin; Logan, Jennifer A.; Yantosca, Robert M.; Singh, Hanwant (Wiley-Blackwell, 2002)
      The atmospheric budget and distribution of acetone are investigated by using a priori estimates of sources and sinks to constrain a global three-dimensional atmospheric model simulation and then using atmospheric observations ...
    • Atmospheric chemistry in the Arctic and subarctic: Influence of natural fires, industrial emissions, and stratospheric inputs 

      Wofsy, Steven Charles; Sachse, G. W.; Gregory, G. L.; Blake, D. R.; Bradshaw, J. D.; Sandholm, S. T.; Singh, H. B.; Barrick, J. A.; Harriss, R. C.; Talbot, R. W.; Shipham, M. A.; Browell, E. V.; Jacob, Daniel James; Logan, Jennifer A. (Wiley-Blackwell, 1992)
      Haze layers with perturbed concentrations of trace gases, believed to originate from tundra and forest wild fires, were observed over extensive areas of Alaska and Canada in 1988. Enhancements of CH, CH, CH, CH, and CH ...
    • Atmospheric distribution of 85 Kr simulated with a general circulation model 

      Jacob, Daniel James; Prather, Michael J.; Wofsy, Steven Charles; McElroy, Michael Brendon (Wiley-Blackwell, 1987)
      A three-dimensional chemical tracer model for the troposphere is used to simulate the global distribution of 85Kr, a long-lived radioisotope released at northern mid-latitudes by nuclear industry. Simulated distributions ...
    • Atmospheric hydrogen cyanide (HCN): Biomass burning source, ocean sink? 

      Li, Qinbin; Jacob, Daniel James; Bey, Isabelle; Yantosca, Robert M.; Zhao, Yongjing; Kondo, Yutaka; Notholt, Justus (Wiley-Blackwell, 2000)
      The observed seasonal amplitude of atmospheric HCN concentrations implies an atmospheric lifetime of only a few months for HCN, much shorter than is commonly assumed from oxidation by OH (a few years). We propose that ocean ...
    • Atmospheric Peroxyacetyl Nitrate (PAN): A Global Budget and Source Attribution 

      Fischer, E. V.; Jacob, Daniel James; Yantosca, Robert M.; Sulprizio, Melissa Payer; Millet, D. B.; Mao, J.; Paulot, F.; Singh, H. B.; Roiger, A.; Ries, L.; Talbot, R. W.; Dzepina, K.; Pandey Deolal, S. (Copernicus GmbH, 2014)
      Peroxyacetyl nitrate (PAN) formed in the atmospheric oxidation of non-methane volatile organic compounds (NMVOCs) is the principal tropospheric reservoir for nitrogen oxide radicals \((NO_x = NO + NO_2)\). PAN enables the ...
    • The atmospheric sulfur cycle over the Amazon Basin: 2. Wet season 

      Andreae, M. O.; Berresheim, H.; Bingemer, H.; Jacob, Daniel James; Lewis, B. L.; Li, S.-M.; Talbot, R. W. (Wiley-Blackwell, 1990)
      We determined the fluxes and concentrations of atmospheric sulfur species at ground level and from aircraft over the Amazon Basin during the 1987 wet season, providing a comprehensive description of the sulfur cycle over ...
    • Background ozone over the United States in summer: Origin, trend, and contribution to pollution episodes 

      Fiore, Arlene M.; Jacob, Daniel James; Bey, Isabelle; Yantosca, Robert M.; Field, Brendan; Fusco, Andrew; Wilkinson, James (Wiley-Blackwell, 2002)
      Observations indicate that ozone (O3) concentrations in surface air over the United States in summer contain a 20–45 ppbv background contribution, presumably reflecting transport from outside the North American boundary ...
    • Biogenic Versus Anthropogenic Sources of CO in the United States 

      Hudman, R.C.; Murray, Lee Thomas; Jacob, Daniel J.; Millet, D.B.; Turquety, S.; Wu, S.; Blake, D.R.; Goldstein, A.H.; Holloway, J.; Sachse, G.W. (American Geophysical Union, 2008)
      Aircraft observations of carbon monoxide (CO) from the ICARTT campaign over the eastern United States in summer 2004 (July 1–August 15), interpreted with a global 3-D model of tropospheric chemistry (GEOS-Chem), show that ...
    • Biogeochemical drivers of the fate of riverine mercury discharged to the global and Arctic oceans 

      Zhang, Yanxu; Jacob, Daniel James; Dutkiewicz, Stephanie; Amos, Helen Marie; Long, Michael Smither; Sunderland, Elynor M (Wiley-Blackwell, 2015)
      Rivers discharge 28 ± 13 Mmol yr1 of mercury (Hg) to ocean margins, an amount comparable to atmospheric deposition to the global oceans. Most of the Hg discharged by rivers is sequestered by burial of benthic sediment in ...
    • Biomass burning emission inventory with daily resolution: Application to aircraft observations of Asian outflow 

      Heald, Colette L.; Jacob, Daniel James; Palmer, Paul; Evans, Mathew; Sachse, Glen; Singh, Hanwant; Blake, Donald (Wiley-Blackwell, 2003)
      We develop a daily-resolved global emission inventory for biomass burning using AVHRR satellite observations of fire activity corrected for data gaps and scan angle biases. We implemented this inventory in a global ...
    • Biomass-burning emissions and associated haze layers over Amazonia 

      Andreae, M. O.; Browell, E. V.; Garstang, M.; Gregory, G. L.; Harriss, R. C.; Hill, G. F.; Jacob, Daniel James; Pereira, M. C.; Sachse, G. W.; Setzer, A. W.; Dias, P. L. Silva; Talbot, R. W.; Torres, A. L.; Wofsy, Steven Charles (Wiley-Blackwell, 1988)
      Biomass-burning plumes and haze layers were observed during the ABLE 2A flights in July/August 1985 over the central Amazon Basin. The haze layers occurred at altitudes between 1000 and 4000 m and were usually only some ...
    • Bromine Chemistry in the Present-Day and Pre-Industrial Troposphere: Implications from Modeling and Satellite Observations 

      Parrella, Justin (2013-02-12)
      This dissertation investigates the impact of bromine on tropospheric ozone, OH, and mercury in the preindustrial and present-day atmosphere through use of modeling and observations from satellite. We developed bromine ...
    • Budgets of reactive nitrogen, hydrocarbons, and ozone over the Amazon forest during the wet season 

      Jacob, Daniel James; Wofsy, Steven Charles (Wiley-Blackwell, 1990)
      The atmospheric composition over the Amazon forest during the wet season is simulated with a onedimensional photochemical model for the planetary boundary layer (PBL) extending from the ground to 2000‐m altitude. The model ...
    • Carboxylic acids in clouds at a high-elevation forested site in central Virginia 

      Keene, William C.; Mosher, Byard W.; Jacob, Daniel James; Munger, J. William; Talbot, Robert W.; Artz, Richard S.; Maben, John R.; Daube, Bruce C.; Galloway, James N. (Wiley-Blackwell, 1995)
      During September 1990 we sampled coarse (>18-μm diameter) and fine (18- to 5.5-μm diameter) droplets and liquid-water content (LWC) in cloud from a tower on a forested ridge top in Shenandoah National Park, Virginia. ...
    • Carboxylic acids in the rural continental atmosphere over the eastern United States during the Shenandoah Cloud and Photochemistry Experiment 

      Talbot, Robert W.; Mosher, Byard W.; Heikes, Brian G.; Jacob, Daniel James; Munger, J. William; Daube, Bruce C.; Keene, William C.; Maben, John R.; Artz, Richard S. (Wiley-Blackwell, 1995)
      The Shenandoah Cloud and Photochemistry Experiment (SCAPE) was conducted during September 1990 in the rural continental atmosphere at a mountain top site (1014 m) in Shenandoah National Park, Virginia. We report here the ...
    • Chemical Cycling and Deposition of Atmospheric Mercury: Global Constraints from Observations 

      Selin, Noelle E.; Jacob, Daniel J.; Park, Rokjin J.; Yantosca, Robert M.; Strode, Sarah; Jaeglé, Lyatt; Jaffe, Daniel (American Geophysical Union, 2007)
      We use a global 3-D model of atmospheric mercury (GEOS-Chem) to interpret worldwide observations of total gaseous mercury (TGM) and reactive gaseous mercury (RGM) in terms of the constraints they provide on the chemical ...
    • Chemical Nonlinearities in Relating Intercontinental Ozone Pollution to Anthropogenic Emissions 

      Wu, Shiliang; Duncan, Bryan N.; Jacob, Daniel J.; Fiore, Arlene M.; Wild, Oliver (American Geophysical Union, 2009)
      Model studies typically estimate intercontinental influence on surface ozone by perturbing emissions from a source continent and diagnosing the ozone response in the receptor continent. Since the response to perturbations ...
    • Chemistry and Transport of Pollution over the Gulf of Mexico and the Pacific: Spring 2006 INTEX-B Campaign Overview and First Results 

      Singh, H. B.; Brune, W. H.; Crawford, J. H.; Flocke, F.; Jacob, Daniel J. (European Geosciences Union, 2009)
      Intercontinental Chemical Transport Experiment-B (INTEX-B) was a major NASA (Acronyms are provided in Appendix A.) led multi-partner atmospheric field campaign completed in the spring of 2006 (http://cloud1.arc.nasa.gov/intex-b/). ...
    • Chemistry of a polluted cloudy boundary layer 

      Jacob, Daniel James; Gottlieb, Elaine W.; Prather, Michael J. (Wiley-Blackwell, 1989)
      A one‐dimensional photochemical model for cloud‐topped boundary layers is developed which includes detailed descriptions of gas‐phase and aqueous‐phase chemistry, and of the radiation field in and below cloud. The model ...