IGSM - Integrated Global System Model
At the heart of the Joint Program's work lies the MIT Integrated Global System Model (IGSM). This comprehensive tool analyzes interactions among humans and the climate system. It is used to study causes of global climate change and potential social and environmental consequences.
Our central research efforts are organized around the IGSM and strive to improve the integratation of climate science, technological change, economics, and social policy analysis into forecasts of the pressing issues in global change science and climate policy.
The MIT IGSM seeks to answer such questions as:
- How effective and costly would specific policy measures be in alleviating climate change?
- What are the advantages and risks of waiting for better scientific understanding of such change?
- How will the oceanic and terrestrial uptake of carbon dioxide and other greenhouse gases be affected by changing climate?
- What nations, regions, and economic sectors are most likely to be affected?
The IGSM consists of three primary submodels:
- Economics, emissions, and policy cost model for analysis of human activity as it interacts with climate processes, and to assess proposed policy measures;
- Climate and Earth system component: coupled dynamic and chemical atmosphere, ocean, land, and natural ecosystem interactions and feedbacks; and
- Land ecosystems and biogeochemical exchanges models, within a Global Land System framework, for analysis of the terrestrial biosphere.
These components then inform a component that analyzes the feedbacks and impacts of climate change. Within the current formulation of the IGSM the consideration of climate change impacts emphasizes terrestrial ecosystems and sea levels, feedbacks of changed climate onto the carbon cycle and natural emissions of CH4 and N2O, effects of climate change and ozone pollution on agriculture, and the interaction of climate chemistry with its counterparts in urban air pollution.
The configuration and capabilities of the IGSM Version 2 are described in Sokolov et al., 2005 (Report 124). An earlier version is documented in Prinn et al. (1999).
The schematic below depicts the current framework and processes of the MIT Integrated Global System Model Version 2 (IGSM2). Solid lines between model components indicate exchanges represented in standard runs of the system; dash-dotted lines indicate model connections that exist and have been utilized in targeted studies; dotted lines indicate areas where implementation of feedbacks is under development.
