The OECD has been using economic models and quantitative assessments since the late 1980s to inform policy makers of the costs, benefits and potential tradeoffs of environmental policies and climate change mitigation scenarios. The main environmental-economic modelling work of the OECD rests upon the in-house models ENV-Linkages, a dynamic general equilibrium model and ENV-Growth, a macroeconomic growth model based on a conditional convergence framework. This modelling work is aimed to assist governments in identifying least-cost policies or policy mixes to reduce greenhouse gas (GHG) emissions, and assesses the cost and impacts of environmental policies and of possible post-2012 international frameworks, among other applications.
Outlooks | Climate change mitigation | Energy | Distributional impacts
The ENV-Linkages model is a recursive dynamic neo-classical general equilibrium model (GE). It is a global economic model built primarily on a database of national economies (GTAP V8 Database). In its current form, the model represents the world economy in 25 countries/regions, each with 22 economic sectors.
The baseline projection as used for the Environmental Outlook to 2050 describes an internally consistent set of trends of all economic and environmental variables of the model. The baseline assumes no new policies for the environmental issues addressed and thus provides a benchmark against which policy scenarios can be assessed.
Summary flyer (pdf)
The ENV-Growth model is a two-sector model that aims at projecting GDP and per capita income levels for all major economies in the world (currently more than 185 countries). The model is based on conditional convergence between countries in the main drivers of economic growth: labour, human capital, physical capital, natural resources and total factor productivity.
ENV-Growth is used in the construction of baseline projections for ENV-Linkages. Furthermore, ENV-Growth is applied to construct macroeconomic projections for the so-called Shared Socioeconomic Pathways (SSPs) for climate change. Preliminary results of these projections are available at https://secure.iiasa.ac.at/web-apps/ene/SspDb.
Summary Flyer (pdf)
OECD Environmental Outlook to 2050 Baseline projection (OECD, 2012)
OECD Environmental Outlook to 2050 Baseline projection (OECD, 2012)
An Economic Projection to 2050: The OECD "ENV-Linkages" Model Baseline
(2011) describes possible future developments and is not a prediction of the future. Rather, it provides an internally consistent set of trends of all economic and environmental variables of the model. The baseline assumes no new policies for the environmental issues addressed and thus provides a benchmark against which policy scenarios can be assessed.
- An overview of the OECD ENV-Linkages Model (2008) presents a summary description of the OECD ENV-Linkages General Equilibrium model. The paper provides a brief description to the structure of the ENV-Linkages model and of its main equations, and describes the calibration method.
- A full description of the ENV-Growth model is forthcoming.
Environmental Outlooks and CIRCLE
The OECD has produced a series of Environmental Outlooks to help policy makers understand the most urgent environmental challenges as well as the economic and environmental implications of the policies that could be used to address these challenges. The CIRCLE project takes the next step and aims at looking at the feedbacks from environmental challenges on economic growth. The Environmental Outlooks and CIRCLE assess a range of important environmental challenges, including climate change, health and environment, loss of biodiversity and ecosystems and water-economy linkages.
The most recent Outlook, the OECD Environmental Outlook to 2050 provides model-based future-oriented analyses of economic and environmental trends in the coming decades. The economic and environmental projections are made possible by combining the ENV-Linkages model at the OECD Environment Directorate with the comprehensive environmental modelling framework of the IMAGE (Integrated Model to Assess the Global Environment) suite of models run by the Netherlands Environmental Assessment Agency (PBL).
More about the OECD Environmental Outlook to 2050 (2012)
The Environmental Outlook to 2050 estimated the costs of selected policy actions. However, these costs of action did not take into account the benefits of these policies. The OECD is currently working on quantifying the costs of inaction as well as the economic benefits of policy action within the project on Costs of Inaction and Resource scarcity: Consequences for Long-term Economic growth (CIRCLE).
Climate change mitigation
The ENV-Linkages model, with its general equilibrium structure, is a powerful tool to analyse the impacts of climate change mitigation policies. Analytical work based on the ENV-Linkages model development spans over a wide range of issues dealing with the interlinkages between environment and the economy: costs and effectiveness of carbon markets, linking of carbon markets, climate change mitigation and employment, climate change mitigation policies and energy policies such as the removal of fossil fuel subsidies.
Highlights of Model Results:
Source: ENV-Linkages Model (2011)
More about OECD Work on Carbon Markets
Climate change mitigation policy and employment
The implementation of a green growth agenda may translate into deep changes in the labour market that extend far beyond the creation of what are often labelled as “green jobs”. While there are a number of opportunities associated with green growth, there are also costs associated with the transition. This topic is analysed in the working paper Employment Impacts of Climate Change Mitigation Policies in OECD: A General-Equilibrium Perspective (2011).
Policies for cost-effective mitigation
Against the background of a projected doubling of world greenhouse gas emissions by mid-century, the book The Economics of Climate Change Mitigation: Policies and Options for Global Action Beyond 2012 (2009) explores through quantitative analysis feasible ways to abate them at least cost.
More about Economics of Climate Change Mitigation
The ENV-Linkages model has traditionally been linked to the IEA World Energy Model (WEM) in order to provide economic impacts of the IEA World Energy Outlooks scenarios. Since 2011, a more sophisticated methodology is used to link these models.
More on the Macroeconomic of energy efficiency using the OECD ENV-Linkages model.
More about OECD Work on Fossil Fuel Subsidies
Distributional impacts of environmental policies
The costs of environmental policies may significantly differ across households, though such policies can give opportunities to reduce poverty and inequalities if combined with appropriate redistribution of the revenues they raise. In order to investigate the impact of environmental policies on poverty and inequalities, the ENV-Linkages model, which in its core specification relies on a single regional representative household, is extended to include - for some regions - an explicit representation of various households groups, differentiated by preferences and incomes sources. This version of the model is used to provide an assessment of the distributional impacts of policy packages where energy subsidy or green tax reforms are implemented.
Permanent URL: www.oecd.org/environment/modelling
OECD work on green growth
OECD Environmental Outlooks
OECD Environment Working Papers
OECD CIRCLE (Costs of Inaction and Resource scarcity: Consequences for Long-term Economic growth) project