The World Induced Technical Change Hybrid model is used and produced by the division CIP (Climate Impacts and Policies. An Economic Assessment), within the macroactivity “Energy and Emission Long Term Scenarios and Mitigation Policies”.

WITCH (World Induced Technical Change Hybrid model) is one of the main modelling tools developed within the FEEM Research Programme “Sustainable Development” and designed to assist in the study of the socio-economic dimension of climate change.

The model has been developed with the aim of studying mitigation and adaptation policies for climate change control. It is currently applied to generate emission scenarios for various international macro-regions, and to evaluate the economic implications of national and international climate agreements, such as Post-Kyoto treaties. The model results have been used in various projects funded by international organizations, as well as governmental agencies and private institutions.

WITCH is a Regional Integrated Assessment Hard-Link Hybrid Model. Its top-down component consists of an intertemporal optimal growth model in which the energy input of the aggregate production function has been expanded to give a bottom-up like description of the energy sector. World countries are grouped in twelve regions that strategically interact following a game theoretic structure. The climate system is described by a climate module and a damage function provide the feedback on the economy of carbon dioxide emissions into the atmosphere. The dynamic and strategic features of the model, the energy sector specification and the technical change options make WITCH an especially suited tool to explicitly analyze the climate change issue, marked by medium term investment choices and long term economic dynamics and environmental responses.

To contact the researchers working on WITCH please write an email to

More information about this model.

Research Papers Other contents Contacts

Valentina Bosetti