June 17, 2005: The SCIDAC CCSM Consortium project has worked closely with the Biogeochemsitry Working Group and the CCSM Software Engineering Group (CSEG) to assemble the components required for a coupled carbon-climate earth system model. This milestone (Q3) is meant to demonstrate that the code for a new model has been assembled. On June 12, 2005 the CSEG group tested and released the alpha version of this software for the SciDAC CCSM Consortium. The code has subsequently been executed on DOE computers at LLBL/NERSC and ORNL/NCCS. The initial test verifies that the components build and execute together using the new coupling mechanisms defined in the Q2 milestone. The code executed on the ORNL IBM p690 system "Cheetah" for ten simulated days, verifying that the modules are linked, required datasets have been provided and the carbon-climate coupling is active as well as the linkages between the oceanic and terrestrial emission of trace species to a fully active atmosphere with interactive chemistry.

The Q3 milestone is a step on the way toward examining the climate response and feedbacks that result from the inclusion of biogeochemical cycles in climate models. We have CO2 moving from the terrestrial biosphere through the coupler into a chemically active atmosphere. The major part of the software design and engineering has been completed and we have conducted the initial tests of an alpha version of the new model. Next steps will involve refinements on the coupling, activation of more tracers, chemical interactions ,careful testing and study of the results. After problems are resolved, a 3-4 year coupled simulation will be performed. A web page will be updated with results and documentation from this effort by the end of the month.