COSE: Compilation of atmospheric observations in support of satellite measurements over Europe

• Research unit: EU RFP
• Project number: 97.0612

Key words (English)

Atmospheric physics; ozone depletion; satellite measurements; remote sensing

Alternative project number (English)

EU project number: ENV4-CT98-0750

Research programs (English)

EU-programme: 4. Frame Research Programme - 3.1 Environment

Short description (English)

See abstract

Partners and International Organizations (English)

BIRA (Brüssel), Alfred Wegener Inst., Uni Liege, CNRS, Uni Bordeaux, Fraunhofer Inst., Uni Bremen, Swedish Env. Res. Inst., NILU (Oslo)

Abstract (English)

COSE provides a validated, consistent and well documented data set of total abundances and vertical distribution profiles of the most important stratospheric constituents which builds on past and ongoing time series, by coordination of ground based observations at existing stations in Europe. Among the major concerns in COSE are a better characterisation of the data content, and an improved scientific return from the experimental data. A dedicated relational database is set up to archive the observations for immediate and future exploitation, e.g. satellite validation activities, data assimilation and scientific studies on a European scale.
Continuous measurements of stratospheric and mesospheric ozone profiles over Bern Switzerland, have been obtained with the Groundbased Ozone Monitoring System (GROMOS). Our data are regularly submitted to the COSE data base.
The main results obtained are the achievement of a study investigating short-time midstratospheric (25 - 40 km) ozone VMR variations observed in the GROMOS data during winter and an updated intercomparison between the microwave and the Payerne Brewer-Mast-balloonsondes ozone profiles between November 1994 and October 1999 .
The first study revealed that the episodes of extreme midstratospheric ozone VMR observed at several occasions over Bern during winter are essentially the result of planetary wave-driven meridional transport. In particular, the influence of photochemical processes was investigated and it was found that photochemistry acts to damp (rather than enhance) the effects of meridional transport.
The intercomparison results showed that a clear discrepancy exists between the coincident microwave and ozonesonde measurements at altitudes above 27 km (~ 18 hPa). A detailed analysis revealed that the discrepancy noticed between the ozonesonde and microwave ozone profiles above 27 km should be rather attributed to erroneous ozonesonde data than to the microwave measurements.
In the timeframe referred to by this report EMCOR (European Minor Constituent Radiometer) has reentered service and has been succesfully operated from the high alpine research station Jungfraujoch. EMCOR has been measuring the water vapour isotope H2(18)O in early winter 1999 and from spring to summer 2000, measurements from which the isotopic composition of water vapour in the stratosphere could be derived for some days in the winter 1999/2000.

References in databases (English)

Swiss Database: Euro-DB of the
State Secretariat for Education and Research
Hallwylstrasse 4
CH-3003 Berne, Switzerland
Tel. [phone]
Swiss Project-Number: 97.0612