Climate, Energy, Water and Land-use Systems (CLEWS) are closely integrated. Yet, most related decision and policy making occurs in disparate institutional entities, informed by relatively disconnected assessments of the individual resource systems. This paper presents the added value of an integrated analytical assessment approach. In doing so, it explicitly values various interdependencies and interactions between CLEWS primarily from an energy sector perspective. The island state of Mauritius was identified as a useful case study given its diverse climate, its increasing water stresses, and its policy focus on reshaping agricultural land-use and reducing fossil fuel imports. Several scenarios to 2030 were defined and analysed to demonstrate the tensions around the CLEWS nexus. Results from an assessment of the energy system with no modelled interlinkages to land-use, energy and water systems are first presented. Then, these are compared to those from an integrated CLEWS assessment. This serves to highlight important dynamics that would have been overlooked without such a systems approach. As an example, the added value of this approach is clearly demonstrated when rainfall reductions are taken into account, and where future land-use changes might occur. (C) 2013 Elsevier Ltd. All rights reserved.

This paper introduces the prototype of new tool which analyses the Climate-, Land-, Energy- and Water- (CLEW) re-sources and their interactions and implications associated with socio-economic development. The presented CLEW model focuses specifically on the analysis of different energy (technology) options and their impact on other resources – e.g. their contribution to climate change, land use change, and water consumption.The CLEW model systematically quantifies trade-offs associated with actions aimed at meeting development goals (specifically energy, food, and water supply) and their impact on the climate, water and environment. The model quantifies resource use with calculations based on collected data, assumptions and user-defined scenarios. Importantly, the model is not limited to internal or national effects but also includes external changes induced through energy imports or exports and land use change. Exemplary, a first preliminary modelling exercise for the island of Mauritius has shown very strong implications on GHG emissions when switching to locally produced biofuels (bio-ethanol) through induced land-use changes and is presented in the second part of this paper.