Intercomparison of simulated transport of CO2 and Rn over Europe with mesoscale models: a concerted action within the AEROCARB project
As part of the EU-funded AEROCARB project, transport simulations with seven different atmospheric transport models were performed and compared among each other and with observations. The purpose of the intercomparison is as a precursor step for the use of the highly resolving models to interpret continental trace gas observations in terms of source and sink processes. The participating models use either observed ecmwf or self-containedly simulated meteorology. They differ in the parameterisations of subgrig-scale processes and the spatio-temporal resolutions. Two models cover the entire globe (TM3 and LMDZ) and were run both with coarse (a few degrees) and high horizontal resolution (up to 0.5 degrees). Three of the models (DEHM, MM5-HANK and REMO-D) with high spatial resolution use a limited domain, (covering either the Eurasian continent or the Northern Hemisphere). These limited area models use time varying CO2 fields as lateral boundary conditions that were previously computed with the global model TM3. All models were forced at the surface with the same land-biosphere CO2 fluxes (3-hourly), air-sea fluxes (monthly) and fossil fuel emissions (yearly)to simulate atmospheric CO2. For the simulation of atmospheric Rn-222 a uniform source over ice-free continents was assumed. The simulations are compared at 9 European stations with continuous measurements of CO2 and Rn. Two periods July 1998 and December 1998 were studied. We will discuss how models differ both for daytime and night time, as well as for the different (biotic, oceanic, fossil)components. We will also evaluate the usefulness of Rn-222 to test daily changes in PBL-free troposphere exchange as well as transport connected with weather systems over the European continents.
AGU Spring Meeting Abstracts
- Pub Date:
- May 2002
- 0315 Biosphere/atmosphere interactions;
- 1615 Biogeochemical processes (4805)