RETRO model boundary conditions

ERA-40: The RETRO reanalysis simulations were constrained with meteorological data from the ERA-40 reanalysis of the European Centre for Medium Range Weather Forecast (ECMWF). For details on how these data were applied, see work package 4.

 

Emissions: The RETRO emission data sets are described here.

 

Methane: In order to prevent a possible drift in methane concentrations with consequences on the simulation of OH and consequently tropospheric ozone, methane concentrations in the boundary layer were prescribed as climatological zonal mean values. A long-term climatology including a future scenario was constructed based on data from the NOAA-ESRL sampling network and the IPCC, 2001 report of IPCC working group 1.

 

Methane boundary conditions
Time series of boundary layer methane concentrations (click to enlarge figure)

 

Stratospheric ozone: The temporal evolution of stratospheric ozone from 1960-2000 was calculated with the FinROSE model by partner FMI. This proved rather difficult because of excessive meridional overturning in the ERA-40 data set. Nevertheless, the agreement between lower stratospheric ozone concentrations from FinROSE and observations from ozone sondes appears reasonable.

 

Stratospheric ozone boundary conditions
Ozone partial pressure monthly mean time series for Payern and Syowa at 177 and 67 hPa levels (click to enlarge figure)

 

 

Boundary conditions data sets