Model scope and methods - MESSAGE-GLOBIOM

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Model Documentation - MESSAGE-GLOBIOM
Corresponding documentation
Model information
Institution International Institute for Applied Systems Analysis (IIASA)
Concept Hybrid model (energy engineering and land use partial equilibrium models soft-linked to macro-economic general equilibrium model)
Solution method Hybrid model (linear program optimization for the energy systems and land-use modules, non-linear program optimization for the macro-economic module)
Anticipation Myopic/Perfect Foresight (MESSAGE can be run both with perfect foresight and myopically, while GLOBIOM runs myopically)

MESSAGE represents the core of the IIASA IAM framework Figure 1 and its main task is to optimize the energy system so that it can satisfy specified energy demands at the lowest costs. MESSAGE carries out this optimization in an iterative setup with MACRO, which provides estimates of the macro-economic demand response that results of energy system and services costs computed by MESSAGE. For the six commercial end-use demand categories depicted in MESSAGE (see Demand of MESSAGE-GLOBIOM), MACRO will adjust useful energy demands, until the two models have reached equilibrium (see Macro-economy section of MESSAGE-GLOBIOM). This iteration reflects price-induced energy efficiency improvements that can occur when energy prices increase.

GLOBIOM provides MESSAGE with information on land use and its implications, like the availability and cost of bio-energy, and availability and cost of emission mitigation in the AFOLU (Agriculture, Forestry and Land Use) sector (see Land-use of MESSAGE-GLOBIOM). To reduce computational costs, MESSAGE iteratively queries a GLOBIOM emulator which can provide possible land-use outcomes during the optimization process instead of requiring the GLOBIOM model to be rerun continuously. Only once the iteration between MESSAGE and MACRO has converged, the resulting bioenergy demands along with corresponding carbon prices are used for a concluding online analysis with the full-fledged GLOBIOM model. This ensures full consistency in the modelled results from MESSAGE and GLOBIOM, and also allows the production of a more extensive set of reporting variables.

Air pollution implications of the energy system are computed in MESSAGE by applying technology-specific pollution coefficients from GAINS (see Pollutants and non-GHG forcing agents for MESSAGE-GLOBIOM and Air pollution and health of MESSAGE-GLOBIOM).

In general, cumulative global GHG emissions from all sectors are constrained at different levels to reach the forcing levels (cf. right-hand side Figure 1). The climate constraints are thus taken up in the coupled MESSAGE-GLOBIOM optimization, and the resulting carbon price is fed back to the full-fledged GLOBIOM model for full consistency. Finally, the combined results for land use, energy, and industrial emissions from MESSAGE and GLOBIOM are merged and fed into MAGICC (see Climate of MESSAGE-GLOBIOM), a global carbon-cycle and climate model, which then provides estimates of the climate implications in terms of atmospheric concentrations, radiative forcing, and global-mean temperature increase. Importantly, climate impacts and impacts of the carbon cycle are currently not accounted for in the IIASA IAM framework. The entire framework is linked to an online database infrastructure which allows straightforward visualisation, analysis, comparison and dissemination of results (Fricko et al., 2016 1).

Figure 1: Overview of the IIASA IAM framework. Coloured boxes represent respective specialized disciplinary models which are integrated for generating internally consistent scenarios. Figure from Riahi et al. (2016).
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References

  1. ^  Oliver Fricko, Petr Havlik, Joeri Rogelj, Zbigniew Klimont, Mykola Gusti, Nils Johnson, Peter Kolp, Manfred Strubegger, Hugo Valin, Markus Amann, Tatiana Ermolieva, Nicklas Forsell, Mario Herrero, Chris Heyes, Georg Kindermann, Volker Krey, David L McCollum, Michael Obersteiner, Shonali Pachauri, Shilpa Rao, Erwin Schmid, Wolfgang Schoepp, Keywan Riahi (2016). The marker quantification of the shared socioeconomic pathway 2: a middle-of-the-road scenario for the 21st century. Global Environmental Change, In press ().