Annex 4 analytical methods

model description

general description

acronym: GAINS

name: Greenhouse Gas and Air Pollution Interactions and Synergies (GAINS)-Model

main purpose: GAINS is an analytical framework for assessing future potentials and costs for reducing air pollution impacts on human health and the environment while simultaneously mitigating climate change through reduced greenhouse gas emissions. It explores synergies and trade-offs in cost-effective emission control strategies so as to maximize benefits across multiple scales.

homepage: http://gains.iiasa.ac.at/models/gains_models4.html

Developer and its nature

ownership: Third-party ownership (commercial companies, Member States, other organisations)

ownership additional info: International Institute for Applied Systems Analysis (IIASA)

is the model code open-source?: NO

Model structure and approach with any key assumptions, limitations and simplifications

details on model structure and approach: —

model inputs: GAINS uses externally produced activity scenarios for the macroeconomic, energy sector and agricultural sector developments. These are imported through links to partial equilibrium models, e.g., PRIMES for energy sector developments in Europe, CAPRI for developments in agricultural activity (livestock numbers and fertilizer use) in Europe, and the IEA-WEO and FAO for global energy and agricultural sector scenarios, respectively. In consistency with respective macroeconomic developments, GAINS generates internally projections for waste generation, relevant industry production, and consumption of F-gases. Technology-specific emission factors and cost parameters are developed internally in GAINS through information from literature and from direct dialogues and iterative consultations with stakeholders.

model outputs

GAINS estimates emissions, mitigation potentials and costs for the major air pollutants (SO2, NOx, PM, NH3, VOC, BC/OC) and for the six greenhouse gases included in the Kyoto Protocol.

Outputs include emissions, impacts and costs of alternative policy configurations, prescribed or identified as cost-effective.

Intended field of application

policy role

The model is designed to contribute to the following policy areas:

Climate action through mitigation potentials for non-CO2 GHGs and Black Carbon
Climate action through harnessing health co-benefits
Public health through air pollution exposure levels
Ecosystem protection through critical loads

GAINS is used for policy analyses under the Convention on Long-range Transboundary Air Pollution (CLRTAP), e.g., for the revision of the Gothenburg Protocol, and by the European Commission for the EU Thematic Strategy on Air Pollution and the air policy review e.g. the EU Clean Air Outlooks (http://gains.iiasa.ac.at/models/gains_resources.html), and it was among the models used to inform the EC proposal “A Clean Planet for All” (COM (2018) 773). GAINS is used to assess domestic mitigation potential of non-CO2 GHGs for EU climate policy analyses. Scientists and government agencies in many nations (e.g., in Europe, China, India, Vietnam) use GAINS as a tool to assess emission reduction potentials in their regions.

In "scenario analysis" mode, it follows emission pathways from sources to impacts, providing estimates of regional costs and the environmental benefits of alternative emission control strategies.

In “optimization” mode, GAINS identifies cost-optimal portfolios of emission control measures for achieving specified targets, such as absolute emission limits, or health impacts.

policy areas

Climate action
Public health

Model transparency and quality assurance

Are uncertainties accounted for in your simulations?: YES - Uncertainty is in GAINS handled through: - The use of alternative activity data scenarios reflecting a range of macroeconomic, energy and agricultural sector developments - Extension of sector/technology model resolution to reflect policy relevant implications of e.g., scale, urban/rural differences, etc. on emission factors and costs - Consideration of a wealth of country-specific factors and circumstances in the derivation of emission factors, cost parameters, and emission control strategies.

Has the model undergone sensitivity analysis?: YES - Sensitivity analyses are frequently performed on GAINS model results on a case-by-case basis, e.g., by the use of alternative activity data scenarios or by using ranges for emission factors and costs in simulations.

Has the model been published in peer review articles?: YES - GAINS model results have been presented in numerous peer-reviewed publications.

Has the model formally undergone scientific review by a panel of international experts?: YES - GAINS has been evaluated by an external expert panel on a few occasions as part of regular IIASA program reviews.

Has model validation been done? Have model predictions been confronted with observed data (ex-post)?: YES - Modelled ambient PM concentrations at (urban or rural) background level have been validated against observations, see Kiesewetter et al (2015a,b) and Amann et al., 2020. GAINS bottom-up emission inventory for global methane emissions evaluated against top-down atmospheric measurements of CH4 concentration, see Höglund-Isaksson et al. (2020); Saunois et al. (2020).

To what extent do input data come from publicly available sources?: Entirely based on publicly available sources

Is the full model database as such available to external users?: YES - The GAINS database is publicly available and can be accessed through the GAINS website. The information supplied on the GAINS website or parts thereof may be freely used for non-commercial and educational purposes. Data from this site is for informational purposes only, and may only be used as input to other models with explicit permission of IIASA. Information from this site may be reproduced with proper acknowledgment to IIASA, Laxenburg, Austria.

Have model results been presented in publicly available reports?: YES

Have output datasets been made publicly available?: NO - Simulation mode results can be produced within the public model framework. Optimization mode results have been made available through peer-reviewed publications.

Is there any user friendly interface presenting model results that is accessible to the public?: YES

Has the model been documented in a publicly available dedicated report or a manual?: YES

Intellectual property rights

Licence type: Non-Free Software licence

application to the impact assessment

Please note that in the annex 4 of the impact assessment report, the general description of the model (available in MIDAS) has to be complemented with the specific information on how the model has been applied in the impact assessment.

See Better Regulation Toolbox, tool #11 Format of the impact assessment report).