UCAM SLIMCAT WP 3'2'2

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UCAM SLIMCATWP 3.2.2
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WP 3.2.2

• WP 3.2.2 Aircraft induced sulphur impact on UTLS
  ozone
• (UCAM-DCHEM)
• Start date 33 End date48
• Participant CEA, UiO, MPICHEM and UCAM-DCHEM
• Objective
• To estimate the effect of aircraft sulphur
  emissions on UTLS ozone
• Description of work
• The impact on ozone of the increase in
  stratospheric aerosol density (SAD) due to
  aircraft sulphur emissions will be calculated.
  Recently published calculations of results from
  one model indicate (Pitari et al., 2002) that the
  downward transport of air depleted in ozone by
  the increased SAD is of the same order of
  magnitude as the ozone production from aircraft
  NOx emissions. This effect needs to be
  investigated with other models, because it is
  highly sensitive to vertical transport in the
  UTLS and to the microphysics implementation. A
  sensitivity study will be performed with several
  ACMs with perturbed and unperturbed stratospheric
  background aerosol climatologies.

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SLIMCAT SAMM

• SLIMCAT (Chippefield 1999) is a 3D CTM primarily
  designed for stratospheric studies. The model use
  18 isentropic levels from 10 to 65 km with the
  bottom layer at ?350K. The model is forced by
  offline meteorological fields from ECMWF or UKMO.
  The horizontal advection scheme uses the second
  order moment scheme (Prather 1996). The vertical
  transport is calculated by the MIDRAD radiation
  scheme. The chemistry module calculates the
  behaviour of 45 species and includes more than
  one hundred photochemical reactions as well as
  nine heterogeneous reactions on PSCs and sulphur
  aerosols. The reaction rates are based on the
  JPL2002 recommendations.
• The Stratospheric Aerosol Microphysical Model
  (SAMM, Tripathi 2004) has been added to SLIMCAT.
  This module simulates homogeneous binary
  nucleation, condensational growth, coagulation,
  and sedimentation of sulphuric acid-water
  particles in order to predict the composition and
  size-distribution of stratospheric aerosols. In
  SAMM, homogeneous nucleation and condensation are
  coupled in a manner that allows realistic
  competition between the two processes for the
  limited amount of vapour. With geometrically
  related size bins (around 40 bins for sulphuric
  acid-water particles in the range 0.3 nm to 1.5 m
  m).
• Recently a new version of the SLIMCAT/TOMCAT
  chemical transport model has been developed in
  combining the existing TOMCAT (tropospheric) and
  SLIMCAT (straospheric) models (Chipperfield
  2005). This extended version of SLIMCAT (using
  ??) will be used in WP 3.2.2 as we want to focus
  on the UTLS and the stratospheric aerosol
  loading.

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2000 fleet(no NOX emission)
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IPCC 1999
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NOx impactSLIMCAT (without SAMM)
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(No Transcript)
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Ozone origin