SAGE
II Aerosol and Ozone Measurements Support for the TRACE P Field
Experiment
Dr.
Charles R. Trepte
NASA Langley
This effort proposes to support TRACE P field
mission planning activities and data analysis and interpretation
of the TRACE P data set with measurements from the SAGE II satellite
experiment. It further
proposes to use TRACE P measurements to aid in the validation of
SAGE II data products in the upper troposphere.
During the TRACE P mission, SAGE II aerosol
and ozone data will be made available to aid mission planning and
post-mission data analysis. SAGE
II will have at least 3 latitudinal sweeps of either SAGE II sunrise
or sunset measurements during the TRACE P deployment and 15 sunrise
and 15 sunset events per day. There
measurements will provide critical information on the vertical
structure of the Asian aerosol plume above 6 km. And enable a more
complete characterization of the aerosol distribution over the
Northern Hemisphere prior to, during and
after completion of the TRACE P field campaign.
Understanding the primary sources and transport
pathways of aerosol in the upper troposphere is the focus of a
study (C. Trepe) sponsored by ACMAP. The
TRACE P measurements offer a range of chemical and gas particle
information that taken in conjunction with dynamical analyses will
enable a fuller understanding of the important aerosol sources
and transport routes.
This proposal will also take advantage of results
from a numerical weather prediction model to complement the isentropic
analysis, which will be provided by Dr. J. Crawford. As
a by-product of Crawford’s simulations, Trepte will make use of
the flow fields, trajectories, and potential vorticity, water vapor
and initialized tracer distributions together with TRACE P data
sets to help identify
locations of aerosol convective mixing and removal and link these
regions to the enhanced aerosol features observed by SAGE II.
SAGE II aerosol data has been well validated
in the stratosphere. Much
less validation has been carried out in the upper troposphere,
partly because of the difficulty in carrying this out in a region
where cloud can occur along the optical path, and partly because
the primary responsibility of the SAGE instrument series has been
to make stratospheric measurements.
Validation of the SAGE measurements of ozone
concentration in the upper troposphere is also needed. TRACE
P will provide measurements with sufficient vertical resolution,
accuracy and coincident registration to verify the retrieved SAGE
II measurements. Prior
SAGE II measurement comparisons to an occasional coincident intersection
with an ozonesonde or comparison with zonal mean averages is inadequate.
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