Project Structure

WP1: Emissions

WP2: Observations

WP3: Sensitivity Studies

WP4: Reanalysis Simulations

WP5: Policy and Impacts

 

RETRO Work Package 2: Collection and Use of Observational Data

The main purpose of this work package was to collect and assess existing observational data sets for the evaluation of the long-term reanalysis simulations. Another important objective was the analysis of past ozone trends based on observational data sets and independent from the model simulations.

 

Four main activities were carried out in this work package:

• Establish a database for observational data including tools for reformatting and documenting the data sets. This database was developed and is hosted at NILU and is described in report D2-2.
• Reanalyse the decadal time series of tropospheric column retrievals from GOME and SCIAMACHY. This work was carried out at the University of Bremen and focused on the analysis of NO2 and formaldehyde columns.
• Assess past trends of tropospheric ozone over Europe based on sonde and early aircraft measurements. This task was carried out at the ETH Zürich and is described in report D2-3 and in two papers available at the Atmospheric Chemistry and Physics web site.
• Review the European startegy for atmospheric observations and make recommendations for the integration of future measurements. The results from this activity are summarized in report D2-2 and report D2-5.

 

Climatological mean ozone profiles in the latitude range 40-60 deg N for the GASP period 1975-1979 as function of potential temperature distance to the dynamical tropopause and season (DJF blue solid line, MAM black dashed line, JJA orange dashed-dotted line, SON red dashed-dot-dotted line). From Schnadt-Poberaj et al., 2007 (click to enlarge figure)

Mean GOME CH2O columns from April 1996 to March 2003. Only centre and west pixels having a cloud fraction less than approximately 20 percent are included. (click to enlarge figure)