HR: 08:00h
AN: A31D-01 [Abstracts]
TI: Chemical Isolation in the Asian Monsoon Anticyclone observed in Atmospheric Chemistry Experiment (ACE-FTS) data
AU: * Park, M
EM: mijeong@ucar.edu
AF: National Center for Atmospheric Research, 3450 Mitchell Lane, Boulder, CO 80301, United
States
AU: Randel, W J
EM: randel@ucar.edu
AF: National Center for Atmospheric Research, 3450 Mitchell Lane, Boulder, CO 80301, United
States
AU: Emmons, L K
EM: emmons@ucar.edu
AF: National Center for Atmospheric Research, 3450 Mitchell Lane, Boulder, CO 80301, United
States
AU: Bernath, P F
EM: pfb500@york.ac.uk
AF: University of Waterloo, Dept of Chemistry
200 University Avenue West, Waterloo, ON N2L 3G1, Canada
AU: Bernath, P F
EM: pfb500@york.ac.uk
AF: University of York, Dept of Chemistry, Heslington, York, YO10 5D, United Kingdom
AU: Walker, K A
EM: kwalker@atmosp.physics.utoronto.ca
AF: University of Waterloo, Dept of Chemistry
200 University Avenue West, Waterloo, ON N2L 3G1, Canada
AU: Walker, K A
EM: kwalker@atmosp.physics.utoronto.ca
AF: University of Toronto, Dept of Physics,
60 St. George Street, Toronto, ON M5S 1A7, Canada
AU: Boone, C D
EM: cboone@acebox.uwaterloo.ca
AF: University of Waterloo, Dept of Chemistry
200 University Avenue West, Waterloo, ON N2L 3G1, Canada
AB:
Evidence of chemical isolation in the Asian monsoon anticyclone is presented using chemical constituents
obtained from the Atmospheric Chemistry Experiment Fourier Transform spectrometer instrument during
summer (June-August) of 2004-2006. Carbon monoxide (CO) shows a broad maximum over the monsoon
anticyclone region in the upper troposphere and lower stratosphere (UTLS); these enhanced CO values are
associated with air pollution transported upward by convection, and confined by the strong anticyclonic circulation.
Profiles inside the anticyclone show enhancement of tropospheric tracers CO, HCN, C2H6, and C2H2 between
~12 to 20 km, with maxima near 13-15 km. Strong correlations are observed among constituents, consistent with
sources from near-surface pollution and biomass burning. Stratospheric tracers (O3, HNO3 and HCl) exhibit
decreased values inside the anticyclone between ~12-20 km. These observations are further evidence of
transport of lower tropospheric air into the UTLS region, and isolation of air within the anticyclone. The relative
enhancements of tropospheric species inside the anticyclone are closely related to the photochemical lifetime of
the species, with strongest enhancement for shorter lived species. Vertical profiles of the ratio of C2H2/CO (used
to measure the relative age of air) suggest relatively rapid transport of fresh emissions up to tropopause level
inside the anticyclone.
DE: 0341 Middle atmosphere: constituent transport and chemistry (3334)
DE: 0368 Troposphere: constituent transport and chemistry
DE: 3360 Remote sensing
DE: 3362 Stratosphere/troposphere interactions
SC: Atmospheric Sciences [A]
MN: 2007 Fall Meeting