GAIM

Global Analysis, Integration and Modelling

The GAIM Task Force began in 1993 with the goal of advancing the study of the coupled dynamics of the Earth system using both observational data and numerical models. GAIM realized that to develop integrated models of the Earth system, it was necessary to evaluate model performance in the context of component Earth system disciplines: atmospheric, oceanic and terrestrial. At that time, it was clear that modeling the carbon cycle was a major gap in climate system modeling and GAIM undertook a series of highly influential activities to fill that need. The evolution of GAIM can be summarized in two phases: (1) a strong focus on independent sub-system analyses of the carbon cycle from 1993-ca 2000, during which several model intercomparison activities evolved including the Potsdam Net Primary Productivity Project (PIK-NPP), Ocean Carbon Model Intercomparison Project (OCMIP), and the Atmospheric Tracer Transport Model intercomparison (TRANSCOM); (2) a transition period from ca. 2000 – 2003 where the original goals were re-visited and activities were initiated to address broader Earth system questions, and the initial development of coupled carbon-climate models (e.g. C4MIP).

There have been a number of other successful activities that were initiated by GAIM, or through GAIM collaboration with other programs. The Global Soil Data Task (2000) was an international collaborative project led by the International Geosphere-Biosphere Programme Data and Information System (IGBP-DIS). The Soil Data System allows users to generate soil information and maps for geographic regions at soil depths and resolutions selected by the user. Derived surfaces of carbon density, nutrient status, water-holding capacity, and heat capacity are provided for modeling and inventory purposes.

Biome 6000 (TEMPO, 1996, Jolly et al., 1998, De Noblet-Ducoudre et al., 2000), was another partnered activity with IGBP-DIS, IGBP-GCTE and IGBP-PAGES. The BIOME 6000 activity has generated global vegetation and mega-biome reconstructions for the mid-Holocene and last glacial maximum as well as regional land surface and aeolian transport and deposition databases.

Integrated Modelling of Human and Environmental Systems