For the outcome of Workpackage 2 that is dealing with extended facets of sustainability a number of complementary satellite models were linked to the core models. Different methodologies to link satellite models were explored. One approach that was analysed in more detail is the decomposition approach. In essence this involves an approximation of the satellite model by numerical differencing. This approach provides a clear-cut interface between the core models and satellite models with two advantages: The information contained in a satellite model of any complexity is condensed in a set of interaction equations that only modestly increase the computational needs of the augmented core model. This methodological approach for dealing with extended sustainability aspects provides a comprehensive and flexible modelling framework for dealing with a wide range of environmental issues. Options to use numerical differencing to link core and extended models of Workpackage 2 were explored.
Linking, thus, the core and extended models in Task 2 required:

• Defining the interface between core models and satellite models for extended sustainability aspects.
• Generating by numerical differencing the interaction equations that describe the link between the two type of models.

• Linking core and extended models

FEEM (lead) with all modelling groups in the Transust.Scan consortium