Intercontinental Transport and Chemical Transformation ITCT

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Intercontinental Transport and Chemical
Transformation (ITCT) An Activity of the
International Global Atmospheric Chemistry
Project (IGAC)
Today (briefly)
The inception of ITCT
Preliminary findings (the scientific basis of
ITCT)
The principle science questions
The strategy and tools
Outline of planned research
(More detailed presentations at this meeting)
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Inception of ITCT
The International Global Atmospheric Chemistry
(IGAC) project was established (1988) to
investigate the impact of chemistry on global
climate change. (ozone and aerosols)
Tokyo Workshop (March 16-17, 2000, Frontier
Research Systems for Global Change). Steering
committee formed white paper accepted by IGAC
ITCT steering committee met (June 6 -7) and
outlined a science plan.
ITCT was formulated with the recognition that
climate change had regional as well as global
dimensions and ozone and aerosols had air
quality, as well as, climate change implications.
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Focus of ITCT
Focus on shorter-lived pollutants ozone,
aerosols. Much of the anthropogenic sources are
in the Northern Hemisphere.
For short-lived species, the ITCZ represents a
line of demarcation that separates the world into
two unique chemical zones the Northern, where
most of the land is, and the Southern, which is
dominated by water.
Since compounds are short-lived, most of the
impact is in the Northern Hemisphere.
The public concern with the chemical aspects of
these species is strongly involved with
air-quality (human and ecosystem impacts as
opposed to climate). ITCT will try to address
both regional climate and air-quality concerns.
White papers available.
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PRELIMINARY FINDINGS The Scientific Basis of
ITCT from a Transatlantic Perspective (c.f.,
Parrish and Jacob this afternoon)
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(No Transcript)
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Identification of controlling meteorology
(Topics described in posters Cooper, McCaffery
and McKeen.)
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(Parrish)
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FUTURE PLANS (Science Questions, Approach, Plans
ITCT from a Transatlantic Perspective)
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THE PRINCIPAL SCIENCE QUESTIONS
What are the export fluxes of oxidants, aerosols,
and their precursors from the Northern
Hemisphere continents to the global atmosphere?
What is the ultimate fate of these substances
exported to the global atmosphere?
What are the impacts of intercontinental
transport in the Northern Hemisphere on surface
air quality?
What are the impacts of changing emissions on
regional and global atmospheric chemistry,
composition, and climate?
What are the impacts of climate variability on
regional and global atmospheric chemistry and
composition?
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THE STRATEGY AND TOOLS
SATELLITE OBSERVATIONS Global and continuous but
few species, low resolution
Question - HOW
3-D CHEMICAL TRACER MODELS
SURFACE OBSERVATIONS high resolution but
spatially limited
AIRCRAFT OBSERVATIONS High resolution, targeted
flights provide critical snapshots for model
testing
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OUTLINE OF PLANNED RESEARCH