Journal article
Convective distribution of tropospheric ozone and tracers in the Central American ITCZ region: Evidence from observations during TC4
Journal of geophysical research. Atmospheres, Vol.115(D10), pp.1FFF-n/a
10/13/2010
DOI: 10.1029/2009JD013450
Abstract
During the Tropical Composition, Clouds and Climate Coupling (TC4) experiment that occurred in July and August of 2007, extensive sampling of active convection in the ITCZ region near Central America was performed from multiple aircraft and satellite sensors. As part of a sampling strategy designed to study cloud processes, the NASA ER-2, WB-57 and DC-8 flew in stacked "racetrack patterns" in convective cells. On July 24, 2007, the ER-2 and DC-8 probed an actively developing storm and the DC-8 was hit by lightning. Case studies of this flight, and of convective outflow on August 5, 2007 reveal a significant anti-correlation between ozone and condensed cloud water content. With little variability in the boundary layer and a vertical gradient, low ozone in the upper troposphere indicates convective transport. Because of the large spatial and temporal variability in surface CO and other pollutants in this region, low ozone is a better convective indicator. Lower tropospheric tracers methyl hydrogen peroxide, total organic bromine and calcium substantiate the ozone results. OMI measurements of mean upper tropospheric ozone near convection show lower ozone in convective outflow. A mass balance estimation of the amount of convective turnover below the tropical tropopause transition layer (TTL) is 50%, with an altitude of maximum convective outflow located between 10 and 11 km, 4 km below the cirrus anvil tops. It appears that convective lofting in this region of the ITCZ is either a two-stage or a rapid mixing process, because undiluted boundary layer air is never sampled in the convective outflow.
Details
- Title: Subtitle
- Convective distribution of tropospheric ozone and tracers in the Central American ITCZ region: Evidence from observations during TC4
- Creators
- Melody Avery - Langley Research CenterCynthia Twohy - Oregon State UniversityDavid McCabe - California Institute of TechnologyJoanna Joiner - Goddard Space Flight CenterKurt Severance - Langley Research CenterEliot Atlas - University of MiamiDonald Blake - University of California, IrvineT. P. Bui - Ames Research CenterJohn Crounse - California Institute of TechnologyJack Dibb - University of New HampshireGlenn Diskin - Langley Research CenterPaul Lawson - SPEC Inc. Boulder Colorado USAMatthew McGill - Goddard Space Flight CenterDavid Rogers - Oregon State UniversityGlen Sachse - National Institute of AerospaceEric Scheuer - University of New HampshireAnne M. Thompson - Pennsylvania State UniversityCharles Trepte - Langley Research CenterPaul Wennberg - California Institute of TechnologyJerald Ziemke - University of Maryland, Baltimore County
- Resource Type
- Journal article
- Publication Details
- Journal of geophysical research. Atmospheres, Vol.115(D10), pp.1FFF-n/a
- Publisher
- Amer Geophysical Union
- DOI
- 10.1029/2009JD013450
- ISSN
- 2169-897X
- eISSN
- 2169-8996
- Number of pages
- 16
- Grant note
- NASA; National Aeronautics & Space Administration (NASA)
- Language
- English
- Date published
- 10/13/2010
- Academic Unit
- Physics and Astronomy; Chemical and Biochemical Engineering
- Record Identifier
- 9984276450302771
Metrics
7 Record Views