Status of v1 BGC Campaign

Each model version is used in a “simulation campaign” consisting of major simulations to address the questions of science drivers in the water cycle, biogeochemistry, and the cryosphere system.

The biogeochemical (BGC) simulations use the lower/standard resolution configuration (100 km atmosphere/land, 30-60-~30 km equator-midlatitudes-poles ocean/sea-ice). The campaign will exercise two different land soil BGC approaches, the Convergent Tropic Cascade (CTC) and the Equilibrium Chemistry Approximation (ECA) configurations, and the simulation campaign will characterize the impacts of the structural uncertainties associated with these different approaches on the model’s coupled carbon-climate feedbacks.

Starting from a spun-up physical state, the representations of biogeochemical processes in land and ocean have been turned on, and the coupled model has been spun up to produce consistent  initial conditions for the physical state and nutrient pools.

Additional simulations are planned to characterize the effect of turning off phosphorus limitation (CTC-CN), and to exercise the model in an emission-forced prognostic CO2 mode (EF).

The spin-up simulations for the CTC model configuration have been completed and production simulations for CTC runs have started, yielding a total of 1130 years of simulations completed by the end of 2018. In the first quarter of 2019, the ECA configuration spin-up was complete and an additional 1039 years of production simulations were performed (559 additional years of CTC simulations and 480 years of ECA simulations). Ten model runs are currently in progress (see the Table below for details). The model configurations (compsets) for the future simulations are close to being finalized and progress has been made on the CTC-CN spin-up.