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Full-Text Articles in Atmospheric Sciences
Transpacific Transport Of Ozone Pollution And The Effect Of Recent Asian Emission Increases On Air Quality In North America: An Integrated Analysis Using Satellite, Aircraft, Ozonesonde, And Surface Observations, D Zhang, D J. Jacob, K F. Boersma, D A. Jaffe, J R. Olson, K W. Bowman, J Worden, A M. Thompson, M A. Avery, Ronald C. Cohen, Jack E. Dibb, F Flocke, H Fuelberg, L Gregory Huey, W W. Mcmillan, H B. Singh, Andrew Weinheimer
Transpacific Transport Of Ozone Pollution And The Effect Of Recent Asian Emission Increases On Air Quality In North America: An Integrated Analysis Using Satellite, Aircraft, Ozonesonde, And Surface Observations, D Zhang, D J. Jacob, K F. Boersma, D A. Jaffe, J R. Olson, K W. Bowman, J Worden, A M. Thompson, M A. Avery, Ronald C. Cohen, Jack E. Dibb, F Flocke, H Fuelberg, L Gregory Huey, W W. Mcmillan, H B. Singh, Andrew Weinheimer
Earth Sciences
We use an ensemble of aircraft, satellite, sonde, and surface observations for April-May 2006 (NASA/INTEX-B aircraft campaign) to better understand the mechanisms for transpacific ozone pollution and its implications for North American air quality. The observations are interpreted with a global 3-D chemical transport model (GEOS-Chem). OMI NO2 satellite observations constrain Asian anthropogenic NOx emissions and indicate a factor of 2 increase from 2000 to 2006 in China. Satellite observations of CO from AIRS and TES indicate two major events of Asian transpacific pollution during INTEX-B. Correlation between TES CO and ozone observations shows evidence for transpacific ozone pollution. The …
Enhanced Secondary Organic Aerosol Formation Due To Water Uptake By Fine Particles, Stephen R. Hennigan, M Bergin, Jack E. Dibb, Rodney J. Weber
Enhanced Secondary Organic Aerosol Formation Due To Water Uptake By Fine Particles, Stephen R. Hennigan, M Bergin, Jack E. Dibb, Rodney J. Weber
Earth Sciences
This study characterizes the partitioning behavior of a significant fraction of the ambient organic aerosol through simultaneous measurements of gas and particle watersoluble organic carbon (WSOC). During the summer in Atlanta, WSOC gas/particle partitioning showed a strong RH dependence that was attributed to particulate liquid water. At elevated RH levels (>70%) a significant increase in WSOC partitioning to the particle phase was observed and followed the predicted water uptake by fine particles. The enhancement in particle-phase partitioning translated to increased median particle WSOC concentrations ranging from 0.3 –0.9 mgCm3 . The results provide a detailed overview of the WSOC …
Simultaneous Measurements Of Particulate And Gas-Phase Water-Soluble Organic Carbon Concentrations At Remote And Urban-Influenced Locations, C Anderson, Jack E. Dibb, Robert J. Griffin, M Bergin
Simultaneous Measurements Of Particulate And Gas-Phase Water-Soluble Organic Carbon Concentrations At Remote And Urban-Influenced Locations, C Anderson, Jack E. Dibb, Robert J. Griffin, M Bergin
Earth Sciences
The sources, sinks, and overall importance of watersoluble organic carbon (WSOC) in the atmosphere are not well understood. Although the primary historical focus has been on particulate WSOC (WSOCP), here we also present results obtained using a newly developed technique that additionally measures gas-phase water-soluble organic carbon (WSOCG). These first-of-their-kind measurements show that WSOCG can often be more than ten times larger than WSOCP at both urban and remote locations. The average fraction of WSOC residing in the gas phase (fg = WSOCG/(WSOCG + WSOCP)) at five various field sites ranged from 0.64 to 0.93, implying significant differences in WSOC …
Analysis Of Aircraft And Satellite Measurements From The Intercontinental Chemical Transport Experiment (Intex-B) To Quantify Long-Range Transport Of East Asian Sulfur To Canada, Aaron Van Donkelaar, R V. Martin, W R. Leaitch, A M. Macdonald, T W. Walker, David G. Streets, Q Zhang, E J. Dunlea, Jose L. Jimenez, Jack E. Dibb, L Gregory Huey, Rodney J. Weber, M O. Andreae
Analysis Of Aircraft And Satellite Measurements From The Intercontinental Chemical Transport Experiment (Intex-B) To Quantify Long-Range Transport Of East Asian Sulfur To Canada, Aaron Van Donkelaar, R V. Martin, W R. Leaitch, A M. Macdonald, T W. Walker, David G. Streets, Q Zhang, E J. Dunlea, Jose L. Jimenez, Jack E. Dibb, L Gregory Huey, Rodney J. Weber, M O. Andreae
Earth Sciences
We interpret a suite of satellite, aircraft, and ground-based measurements over the North Pacific Ocean and western North America during April–May 2006 as part of the Intercontinental Chemical Transport Experiment Phase B (INTEX-B) campaign to understand the implications of long-range transport of East Asian emissions to North America. The Canadian component of INTEX-B included 33 vertical profiles from a Cessna 207 aircraft equipped with an aerosol mass spectrometer. Long-range transport of organic aerosols was insignificant, contrary to expectations. Measured sulfate plumes in the free troposphere over British Columbia exceeded 2 μg/m3. We update the global anthropogenic emission inventory in a …
Local Anthropogenic Impact On Particulate Elemental Carbon Concentrations At Summit, Greenland, Gayle S.W. Hagler, M Bergin, E A. Smith, M Town, Jack E. Dibb
Local Anthropogenic Impact On Particulate Elemental Carbon Concentrations At Summit, Greenland, Gayle S.W. Hagler, M Bergin, E A. Smith, M Town, Jack E. Dibb
Earth Sciences
Summit, Greenland is a remote Arctic research station allowing for field measurements at the highest point of the Greenland Ice Sheet. Due to the current reliance on diesel generators for electricity at Summit, unavoidable local emissions are a potential contamination threat to the measurement of combustion-related species in the air and snow. The effect of fossil-fuel combustion on particulate elemental carbon (EC) is assessed by a combination of ambient measurements (∼1 km from the main camp), a series of snow pits, and Gaussian plume modeling. Ambient measurements indicate that the air directly downwind of the research station generators experiences particulate …
The Impact Of Local Sources And Long-Range Transport On Aerosol Properties Over The Northeast U.S. Region During Intex-Na, K L. Thornhill, Gao Chen, Jack E. Dibb, C. Jordan, Ali Omar, E L. Winstead, Greg Schuster, A D. Clarke, Cameron Mcnaughton, Eric Scheuer, D R. Blake, Glen Sachse, L Gregory Huey, H B. Singh, Bruce E. Anderson
The Impact Of Local Sources And Long-Range Transport On Aerosol Properties Over The Northeast U.S. Region During Intex-Na, K L. Thornhill, Gao Chen, Jack E. Dibb, C. Jordan, Ali Omar, E L. Winstead, Greg Schuster, A D. Clarke, Cameron Mcnaughton, Eric Scheuer, D R. Blake, Glen Sachse, L Gregory Huey, H B. Singh, Bruce E. Anderson
Earth Sciences
We use data collected aboard the NASA DC-8 aircraft during the summer 2004, Intercontinental Transport and Chemical Evolution Experiment over North America (INTEX-NA) field campaign to examine the origin, composition, physical and optical properties of aerosols within air masses sampled over and downwind of the northeastern U.S. We note that aerosol concentrations within the region exhibited steep vertical gradients and significant variability in both time and space. An examination of air mass chemical signatures and backward trajectories indicates that transport from four, significantly different source regions contributed to the variability: the subtropical Atlantic Ocean (AO); the U.S. west coast and …
Factors Influencing The Large-Scale Distribution Of Hg° In The Mexico City Area And Over The North Pacific, Robert W. Talbot, Huiting Mao, Jack E. Dibb, M A. Avery, E V. Browell, G W. Sachse, S Vay, D R. Blake, L Gregory Huey, H Fuelberg
Factors Influencing The Large-Scale Distribution Of Hg° In The Mexico City Area And Over The North Pacific, Robert W. Talbot, Huiting Mao, Jack E. Dibb, M A. Avery, E V. Browell, G W. Sachse, S Vay, D R. Blake, L Gregory Huey, H Fuelberg
Earth Sciences
Gas-phase elemental mercury (Hg°) was measured aboard the NASA DC-8 aircraft during the Intercontinental Chemical Transport Experiment Phase B (INTEX-B) campaign in spring 2006. Flights were conducted around Mexico City and on two subsequent deployments over the North Pacific based out of Honolulu, Hawaii and Anchorage, Alaska. Data obtained from 0.15–12 km altitude showed that Hg° exhibited a relatively constant vertical profile centered around 100 ppqv. Highly concentrated pollution plumes emanating from the Mexico City urban agglomeration revealed that mixing ratios of Hg° as large as 500 ppqv were related to combustion tracers such as CO, but not SO2 which …