ESA-ESRIN, Frascati, Rome, Italy
18th – 29th August 20031
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Scientific Objectives of SPARC*
and the Value of Data Assimilation
Alan O’Neill
Data Assimilation Research Centre
University of Reading
*Stratospheric Processes and their Role in Climate:
a project of the World Climate Research Programme
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Aim of SPARC
• To bring stratospheric expertise to bear on scientific issues concerned with climate processes and climate prediction;
• for the benefit of– World Climate Research Programme – WMO/UNEP Ozone Assessment– IPCC– Space Agencies
ESA-ESRIN, Frascati, Rome, Italy
18th – 29th August 20032
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SPARC Stratospheric Processes and their Role in Climate
• Research project (est. 1992) of the WCRP.• Focuses on role of stratospheric dynamical,
chemical and radiative processes of the troposphere-stratosphere system:– Influence of stratosphere on climate
– Physics & chemistry of ozone depletion
– Stratospheric variability and monitoring
– Changes in UV radiation
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Web Site
http://www.aero.jussieu.fr/~sparc
ESA-ESRIN, Frascati, Rome, Italy
18th – 29th August 20033
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1979-1994
2σ uncertainty
Compiled using radiosonde, satellite and analysed data sets
Mean vertical profile of annual & decadal temperature trend at 45oN.
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ESA-ESRIN, Frascati, Rome, Italy
18th – 29th August 20038
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Stratospheric Chemistry
and Climate
Stratosphere-Troposphere coupling
Detection and Attribution of Past Stratospheric Changes
Model
Development
Process
StudiesData
Future Themes
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Stratospheric Chemistryand Climate
• How will stratospheric ozone and other constituents evolve?
• How will changes in stratospheric composition affect climate?
• What are the links between changes in stratospheric ozone, UV radiation and tropospheric chemistry?
ESA-ESRIN, Frascati, Rome, Italy
18th – 29th August 20039
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Ozone-trends and with Chemistry on condensed matter
T ropospher e
St ratosphere
Cl ClO
In-situ O3 destruction
CirrusprocessingForcing by
Weather Systems
Other DynamicalForcings Contributions from
polar processed air
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ASAPAssessment of Stratospheric Aerosol Processes
Aerosol Processes
Precursor Gases
Modeling
Trend Analysis
Aerosol Record
El Chichón Pinatubo
ASAP – The SPARC Aerosol Assessment
ESA-ESRIN, Frascati, Rome, Italy
18th – 29th August 200310
Long timescaleLong timescale
§Why does the AO tend to become negative after sudden warmings?
§How could this relationship be used to forecast the AO index?
§Is the effect confined to extreme events in the stratosphere, oris there a linear relationship between the stratospheric NAM and the future AO index?
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ESA-ESRIN, Frascati, Rome, Italy
18th – 29th August 200311
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SPARC Data Assimilation initiative
ESA-ESRIN, Frascati, Rome, Italy
18th – 29th August 200312
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Data Assimilation Working Grou
• Collect information on stratospheric data sets on meteorology and chemistry (quality, availability, software…).
• Process-focused quality assessments.• Collect and document information in
data assimilation systems.• Liaise with space and other agencies on
SPARC data needs.
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End