Project Structure

WP1: Emissions

WP2: Observations

WP3: Sensitivity Studies

WP4: Reanalysis Simulations

WP5: Policy and Impacts

 

RETRO Work Package 3: Preparatory Runs and Sensitivity Studies

In the original work plan of the project, this work package was intended to monitor the quality of the model simulations with new emission data and boundary conditions before beginning the long-term reanalysis simulations and to conduct sensitivity studies based on the reanalysis results. Due to delays in the production of these data sets, the studies carried out in work package 3 became somewhat more independent from the reanalysis simulations and the model results are sometimes different due to a different set-up of the experiments.

 

The work focused on three aspects to characterize the model performance:

• Analysis of seasonal variations (see report D3-2
• Sensitivities of trends and interannual variability to emissions, chemistry and dynamics (see report D3-3
• Analysis of specific processes (stratospheric intrusion, long-range transport and Indonesian forest fires; see report D3-4

 

Seasonal cycle in the tropospheric NO2 column density over the Eastern United States from three different retrievals of the GOME instrument and from three of the RETRO models. From van Noije et al., 2006 (click to enlarge figure)

Fraction of ozone originating from the stratosphere during a stratospheric intrusion event over Mauna Loa, Hawaii, in February 1997. From report D3-4 (click to enlarge figure)

 

 

Furthermore, this work package was concerned with the development of software tools and the definition of suitable metrics for the model evaluation (described in report D3-2).

 

Finally, work package 3 organized participation of all five RETRO models in the ACCENT/IPCC Photocomp 2030 multi-model experiment to investigate changes in future ground-level ozone levels. The results from this activity were published in a series of papers in 2006 and 2007 (see article list).