The overall strategy chosen here includes two phases. The 1st phase makes use of existing ESMs to produce simulations based on the CMIP5 protocol for IPCC AR5 and to incorporate new model components and to test the resulting new ESM. The ESMs ready at the beginning of the project will be used for decadal and centennial climate change simulations, and data of these simulations will be analyzed and submitted to the CMIP5 data archives before the deadline set by IPCC for AR5. These standardised simulations will be used as a reference for the 2nd phase simulations using the new ESMs built in the 1st phase of the project. Data of the 1st and 2nd phase will be compared to isolate the single and combined effects of the new components on decadal climate predictability and on climate feedback mechanisms. The data will be analysed for the physical climate change and socio economic impacts on the global and regional scale. Revised scenarios will result from the combined use of ESM climate projections and integrated assessment modelling. This strategy allows COMBINE to make progress in the understanding of the functioning of the Earth system and in Earth system modelling, and at the same time COMBINE will be able to contribute significantly to the 5th assessment report for IPCC and to support scientifically the EC and other governing bodies for future climate protection policies. This workflow is depicted in the Pert diagram shown below.