PAGE simulates the economic and environmental impact of policies to address climate change.
The current verison of the Climate CoLab uses only a single module of PAGE, the one that assesses the economic cost of damages caused by climate change.
PAGE overview#Model name Policy Analysis of the Greenhouse Effect (PAGE)
Brief description PAGE projects future increases in global mean temperature (GMT), the economic costs of damages caused by climate change, the economic costs of mitigation policies, and the overall impage of adaptation measures (including costs of adaptation measures and reduction in damage costs that results from adaptation).
Model developer(s) Chris Hope (with John Anderson, Paul Wenman, and Erica Plambeck)
Institutional affiliation of developer(s) Judge Business School, University of Cambridge
Date created 1991
Date of most recent revision 2002 (updated version known as PAGE2002)
Model is run in developer's lab to test various policy scenarios, with results published extensively (see list of publications below).
Chris Hope. 2006. The Marginal Impact of CO2 from PAGE 2002. Integrated Assessment Journal 6 (1): 9-56.
Simon Dietz, Chris Hope, Nicola Patmore. 2007. Some economics of 'dangerous' climate change: Reflections on the Stern Review. Global Environmental Change 17 (3-4): 311-325.
Nicholas Stern. 2006. The Economics of Climate Change: The Stern Review, chapter 6, Economic modelling of climate-change impacts. London: HM Treasury.
Erica Plambeck and Chris Hope. 1996. PAGE95: An updated valuation of the impacts of global warming. Energy Policy 24 (9): 783-793.
Chris Hope, John Anderson and Paul Wenman. 1993. Policy analysis of the greenhouse effect: An application of the PAGE model. Energy Policy 21 (3): 327-338.
PAGE attributes#Model type Damage function module of an integrated assessment model.
Geographic scope Global
8 regions (European Union, Eastern Europe and former Soviet Union, China and Centrally Proposalned Asia, India and Southeast Asia, Africa and Middle East, Latin America, Other OECD)
Start date 2000
End date 2200
Time step Various (analysis years are 2000, 2001, 2002, 2010, 2200, 2040, 2060, 2080, 2100, 2150, 2200)
The PAGE damage function relies heavily on estimates prepared by IPCC Working Group II for the Third Assessment Report (TAR). See IPCC. 2001. Climate change 2001: Impacts, adaptation, and vulnerability, Contribution of Working Group II to the Third Assessment Report of the Intergovernmental Panel on Climate Change. In particular, it makes use of chapter 19, Vulnerability to Climate Change and Reasons for Concern: A Synthesis
Approach for addressing risk/uncertainty
PAGE is a stochastic model. 31 of its key input variables are defined not by a single value, but rather, as a probability distribution comprised of a range of possible values. For each such variable a minimum, maximum, mean, and mode is defined.
Each time the model analyzes a new scenario, it is run 1000 times, with the value of the uncertain variables selected randomly for each run.
The 1000 model runs result in 1000 values for each key output variable. These results are typically reported in a probabilistic manner. The mean, or average, result is typcially reported. And sometimes two other values are used to show the shape of the distribution: the value for which 5% of the runs are lower and for which 95% of the runs are lower (hese are called the 5% and 95% values).
Key modules and linkages between them
In the PAGE model, the overall damages from climate change are derived by combining four factors:
* Costs of damages to economic activity caused by climate change
* Costs of non-economic damages caused by climate change
* Costs of large-scale discontinuities
* Impact of mitigation (costs of mitigation measures less reduction in damages resulting from mitigation measures)