HR: 0800h
AN: A51C-0063    [Abstracts]
TI: An Examination of Photochemistry Based on INTEX-NA Observations
AU: * Olson, J R
EM: j.r.olson@larc.nasa.gov
AF: NASA Langley Research Center, Mail Stop 401B, Hampton, VA 23681 United States
AU: Crawford, J
EM: j.h.crawford@larc.nasa.gov
AF: NASA Langley Research Center, Mail Stop 401B, Hampton, VA 23681 United States
AU: Chen, G
EM: gao.chen-1@nasa.gov
AF: NASA Langley Research Center, Mail Stop 401B, Hampton, VA 23681 United States
AU: Brune, W
EM: brune@essc.psu.edu
AF: Penn State University, Department of Meteorology 504 Walker Building, State College, PA 16802 United States
AU: Ren, X
EM: xur1@psu.edu
AF: Penn State University, Department of Meteorology 504 Walker Building, State College, PA 16802 United States
AU: Cohen, R
EM: cohen@cchem.berkeley.edu
AF: UC Berkeley, 420 Latimer Hall, Berkeley, CA 94720 United States
AU: Bertram, T
EM: tbertram@uclink.berkeley.edu
AF: UC Berkeley, 420 Latimer Hall, Berkeley, CA 94720 United States
AU: Fried, A
EM: fried@ucar.edu
AF: NCAR, P.O. Box 3000, Boulder, CO 80307 United States
AU: Walega, J
EM: walega@ucar.edu
AF: NCAR, P.O. Box 3000, Boulder, CO 80307 United States
AU: Heikes, B
EM: zagar@notos.gso.uri.edu
AF: University of Rhode Island, Graduate School of Oceanography, Kingston, RI 02881 United States
AU: O'Sullivan, D
EM: osulliva@usna.edu
AF: U.S. Naval Academy, 121 Blake Road, Annapolis, MD 21402 United States
AU: Huey, G
EM: greg.huey@eas.gatech.edu
AF: Georgia Tech, School of Earth and Atmospheric Sciences, Atlanta, GA 30332 United States
AU: Wennberg, P
EM: wennberg@gps.caltech.edu
AF: California Institute of Technology, 1200 East California Blvd, Pasadena, CA 91125 United States
AU: Crounse, J
EM: crounjd@caltech.edu
AF: California Institute of Technology, 1200 East California Blvd, Pasadena, CA 91125 United States
AU: Kwan, A
EM: kwan@caltech.edu
AF: California Institute of Technology, 1200 East California Blvd, Pasadena, CA 91125 United States
AB: Measurements made from the NASA DC8 aircraft over the North American continent and just off its east coast during the summertime 2004 INTEX-NA campaign provide an unprecedented array of photochemical observations for evaluation. This presents the opportunity for detailed analysis of photochemistry over a region that is influenced by significant urban and industrial pollution. The upper tropospheric environment is further influenced by convection and lightning production of NOx. A photochemical box model constrained by INTEX-NA observations of long-lived gases is used to predict radical concentrations. Radical predictions are then compared to measurements to test the fidelity of current photochemical theory, subject to the assumption that concentrations are controlled by local photochemistry. Analysis of the INTEX-NA data shows that discrepancies in the model-to-measurement comparison exist for several trace gases, including HO2 and other species that are dependent on HOx (e.g., peroxides, pernitric acid, aldehydes). While in some cases, discrepancies in the form of model underprediction can be explained by the neglect of convective transport, in many cases, discrepancies are contradictory between the species. Further, for some species such as peroxyacetic acid (PAA) and acetaldehyde, both photochemistry and convective transport fall well short of explaining observed upper tropospheric concentrations.
DE: 0300 ATMOSPHERIC COMPOSITION AND STRUCTURE
DE: 0345 Pollution: urban and regional (0305, 0478, 4251)
DE: 0365 Troposphere: composition and chemistry
DE: 0368 Troposphere: constituent transport and chemistry
SC: Atmospheric Sciences [A]
MN: Fall Meeting 2005