HR: 13:40h
AN: A53D-01    [Abstracts]
TI: Stratospheric Influence on the Composition of the Mid- and Upper- Troposphere Over North America During INTEX
AU: * Dibb, J E
EM: jack.dibb@unh.edu
AF: CCRC/EOS University of New Hampshire, Morse Hall, 39 College Road, Durham, NH 03824 United States
AU: Scheuer, E
EM: eric.scheuer@unh.edu
AF: CCRC/EOS University of New Hampshire, Morse Hall, 39 College Road, Durham, NH 03824 United States
AU: Avery, M
EM: m.a.avery@larc.nasa.gov
AF: NASA Langley Research Center, Mail Stop 483, Hampton, VA 23681 United States
AB: Intensive sampling from multiple airborne platforms during the ICARTT campaign in summer 2004 has demonstrated that the composition of the North American free troposphere is influenced by multiple sources. Properly identifying and accounting for the contributions from anthropogenic sources in North America (lifted in association with fronts, or pumped in deep convection), lightning generated NO_x, emissions from extensive wild fires in Alaska and Canada, Asian pollution transported across the Pacific, and stratospheric air injected into the troposphere is a challenge that is being addressed with multiple analytical approaches (see several other papers in this session). We use correlations between nitric acid, Be-7, and ozone measured from the NASA DC-8 during INTEX to constrain the stratospheric contribution to the tropospheric burdens of nitric acid and ozone. Our analysis is limited by the availability of Be-7 data, but suggests that the stratospheric source of nitric acid is dominant in the upper troposphere and significant as low as the 5 to 8 km altitude range.
DE: 0300 ATMOSPHERIC COMPOSITION AND STRUCTURE
DE: 0365 Troposphere: composition and chemistry
DE: 0368 Troposphere: constituent transport and chemistry
DE: 3362 Stratosphere/troposphere interactions
SC: Atmospheric Sciences [A]
MN: Fall Meeting 2005