EMF OP 48: Preliminary Results from EMF 14 on Integrated Assessment of Climate Change

A historic Framework Convention onClimate Change was signed by 154 countries at the United NationsConference on Environment and Development (UNCED) in Brazil in June1992. A goal of the convention was to have countries work towardsstabilizing concentrations of greenhouse gases in the atmosphere at alevel that would prevent undesirable anthropogenically induced effectson the climate system. Ultimately, the appropriate course of action foreach country will depend on its assessment of the costs and benefits ofpolicy intervention.

There remain large uncertainties, however, about likely greenhouse gasemission levels in the future, about the relationship between emissionsof greenhouse gases and their atmospheric concentrations, about thelink between atmospheric concentrations and global climate change,about the changes in climate that will occur, about the impacts of theclimate change on people and ecosystems, and about how these impactsought to be evaluated. Over the past few years a number of “integratedassessment” models that represent these links have been developed. Thepurpose of this EMF study was to compare the various approaches to“integrated assessment” that have been employed to assess theirusefulness (and recommend areas for improvement) in policy developmentand in setting climate change research priorities.

The study brought together representatives of “integrated assessment”modeling teams with experts (with or without models) on each of the keyindividual components and linkages (e.g. carbon cycle, atmosphericchemistry, climate, energy-economics, physical impacts of climatechange, valuation of impacts, etc.). Working with individuals involvedin the development of policies for dealing with climate change, thesegroups have run mutually agreed upon standardized scenarios and havecompared key outputs produced. Because of its interdisciplinary natureand the complexities involved, this study required more component bycomponent comparisons than previous EMF studies, as well as a closerlook at the way model components are currently linked, and anassessment of whether or not improved linkages/component setscan/should be developed in the future.

The full EMF 14 working group met five times: (1) in June of 1994 inWashington D.C., (2) in December of 1994 at the International Institutefor Applied Systems and Analysis outside Vienna Austria; (3) in May of1995 at Stanford University; (4) in March 1996 at IIASA, and (5) inMarch 1997 in Tokyo, Japan. In addition, numerous study group meetingswere convened between mid-1994 and mid-1997.