Climate and Atmospheric Composition Model

The Integrated Science Assessment Model (ISAM) is a global model of greenhouse gas cycles and the climate system capable of being used in the Integrated Population-Economy-Technology-Science (iPETS) model that underlies the work of the Integrated Assessment Modeling (IAM) group at the National Center for Atmospheric Research (NCAR). There are several versions of ISAM, with varying degrees of complexity, ranging from a simple globally aggregated model to a spatially explicit terrestrial model coupled with a 2.5 dimensional ocean model with representations of ocean biogeochemistry and sea ice. Currently iPETS links the Population-Environment-Technology (PET) model with the simpler version of ISAM, which includes a simple climate model and globally aggregated carbon cycle model, with reduced form representations of other greenhouse gases. Work is underway to link to more complex terrestrial and climate models, including both ISAM and the NCAR Community Land Model (CLM).

Background Information

ISAM was developed by Atul Jain and colleages at the University of Illinois Department of Atmospheric Sciences. The model was designed to take projections of human emissions of carbon dioxide, other greenhouse gases, and air pollutants and generate predictions of future greenhouse gas and aerosol concentrations, global climate change, and impacts of climate change.

Additional Information

Documentation for the principal components of the globally-aggregated version of ISAM can be found in Jain et al. (1995) and Kheshgi et al. (1996).