IPCC Expert Meeting Addresses Assessing and Combining Multi-Model Climate Projections

January 2010: The Intergovernmental Panel on Climate Change (IPCC) convened an expert meeting on Assessing and Combining Multi-Model Climate Projections from 25-27 January 2010, in Boulder, US. The meeting was held under the auspices of IPCC Working Groups (WGs) I (Physical Science Basis and Impacts) and II (Adaptation and Vulnerability).

The outcomes of the meeting will feed into the Fifth Assessment Report (AR5), which is due in 2013-2014. Climate model results provide the basis for IPCC projections of future climate change. Previous assessment reports included model evaluations but avoided weighting or ranking models. This joint WG I and II expert meeting addressed possible ways of analysing and evaluating model results in order to provide more robust and reliable projections of future climate, along with improved estimates of uncertainty.

The expert meeting provided guidance on dealing with multi-model analysis through keynote presentations, poster sessions and discussions both in breakout groups and plenary. Topics under consideration included methods of such analysis, spatial and temporal applications, specific user needs, and feasibility and implications. Discussions also focused on the provision of information for the Atlas of Global and Regional Climate Change Projections, which is an important new feature of the WG I contribution to the AR5. Around 50 experts from both WGs participated in the meeting, providing a range of expertise from the climate modelling, impacts and user communities.

A meeting report will be published in the second quarter of 2010, which will include a short Guidance Paper for the use of the authors of the respective chapters of WGs I and II in the AR5, and for the WG I and WG II research communities in general. [Meeting Website]