Decomposing Air Pollutant Emissions in Asia: Determinants and Projections

High levels of air pollution pose an urgent social and public health challenge in many Asian regions. This study evaluates the role of key factors that determined the changes in emission levels in China, India and Japan over the past 25 years. While emissions of air pollutants have been declining in Japan since the 1990s, China and India have experienced a rapid growth in pollution levels in recent years. Around 2005, control measures for sulfur emissions started to deliver expected reductions in China, followed by cuts in nitrogen oxides ten years later. Despite recent policy interventions, growing emission trends in India persist. A decomposition analysis of emission-driving factors indicates that emission levels would have been at least two-times higher without the improvements in energy intensity and efficiency, combined with end-of-pipe measures. Due to the continuous reliance on fossil fuels, the abatement effect of a cleaner fuel mix was in most cases significantly smaller than other factors. A reassessment of emission projections developed in the past suggests a decisive impact of energy and environmental policies. It is expected that targeted legislative instruments will play a dominant role in achieving future air-quality goals in Asia

The Role of Non-CO2 Gases in Flexible Climate Policy: An Analysis with the Energy-Systems GMM Model

This paper examines the effects of incorporating two main non-CO2 greenhouse gases, namely methane (CH4) and nitrous oxide (N2O) into the "bottom-up", partial equilibrium, energy-systems Global Multi-regional MARKAL model (GMM). Abatement possibilities for these two greenhouse gases have been included using marginal abatement curves from the U.S. EPA study (2003). Our results illustrate the effect of these greenhouse gases on the composition of emissions mitigation strategies and associated costs, highlighting the importance of the "what" flexibility in climate-change policies. In addition, we emphasize the influence of assumptions regarding rate of deployment and technological change in non-CO2 abatement potentials on the model's outcome

GHG Mitigation Potentials in Annex I Countries. Comparison of Model Estimates for 2020

Robust quantification of the future potentials and costs for mitigating greenhouse gases in different countries could provide important information to the current negotiations on a post-2012 climate agreement. However, such information is not readily available from statistical sources, but requires the use of complex models that combine economic, technological and social aspects. In March 2009, the International Institute for Applied Systems Analysis (IIASA) invited leading modelling teams to a comparison of available model estimates of GHG mitigation potentials and costs in the Annex I countries for the year 2020. Eight modelling teams provided input to this comparison exercise. Although at face value estimates of mitigation potentials and costs show wide variation across models differences (i) in assumptions on the baseline economic development, (ii) in the definition of which mitigation measures are considered part of the baseline, and (iii) in the time window assumed for the implementation of mitigation measures explain much of the variation in model results. The paper presents a check-list of factors that need to be considered when interpreting model results. Once corrected for these key factors, two clusters of cost curves emerge for the year 2020: Models that include consumer demand changes and macro-economic feedbacks agree on a mitigation potential of up to 40% reduction below 2005 levels (that is approximately 45% below the 1990 level) for total Annex I emissions in 2020 for a carbon price of 50 to 150 US-$/tCO2. Bottom-up models that restrict their analysis to technical measures show only half of this potential. The model intercomparison demonstrates that future economic development has a strong impact on the eforts necessary to achieve given emission reduction levels. Any delay in the start of implementation of mitigation measures will reduce the mitigation potential that is achievable in the near term and inrease the costs. The introduction of measures that mobilize demand adjustments through structural or behavioural changes may increase the short-term mitigation potential significantly

GHG Mitigation Potentials from Energy Use and Industrial Sources in Annex I Countries: Methodology

This report documents the basic methodology of IIASA's GAINS model that has been used for comparing mitigation potentials for energy related and industrial emissions across Annex I Parties. Additional information sources are available at gains.iiasa.ac.at/Annex1.htm

GHG Mitigation Potentials and Costs in the Transport Sector of Annex I Countries: Methodology, Version 2

This report documents the specific methodology of IIASA's GAINS model for emissions from transport activities that has been used for comparing mitigation efforts across Annex I Parties. Additional information sources are available at gains.iiasa.ac.at/Annex1.htm

A policy review of synergies and trade-offs in South African climate change mitigation and air pollution control strategies

Climate change mitigation and air quality management are mostly addressed separately in South African legal acts and policies. This approach is not always coherent, especially in the context of other serious issues South Africa is facing, suh as poverty alleviation. Policies implemented to mitigate climate change might increase negative health affects due to unanticipated outcomes (e.g. increased local air pollution), and these indirect consequences must therefore be taken into account when devising mitigation strategies. However, greenhouse gas mitigation policies can also have co-benefits and positive impacts on local air pollution. An evidence-based approach that takes into account greenhouse gas emissions, ambient air pollutants, economic factors (affordability, cost optimisation), social factors (poverty alleviations, public health benefits), and political acceptability is needed tackle these challenges. A proposal is made that use of an integrated climate/air pollution techno-economic optimising model, such as the Greenhouse Gas and Air Pollution Synergies (GAINS) model, may provide a rational decision support tool to guide policy makers into effective strategies for combined Climate Change and Air Quality mitigation measures

GAINS: The impact of economic crisis on GHG mitigation potentials and costs in Annex I Countries

This report analyzes how GHG mitigation potentials and costs in the Annex I countries of the UNFCCC are influenced by the current economic crisis

Assessing emissions levels and costs associated with climate and air pollution policies in South Africa

Affordable energy supply and reductions in emissions of local air pollution and greenhouse gases are each important aspects of South Africa's goals. Many traditional solutions, however, work in contradiction to one another. This work investigates effects on estimated emissions and costs of mitigation strategies using the Greenhouse Gas and Air Pollution Interaction Synergies (GAINS) model to identify policies that satisfy multiple goals. Eight scenarios that describe air pollution control options and mixes of energy production technologies are implemented in GAINS, which quantifies country-wide air pollution and greenhouse emissions and costs of controls. Emissions and costs trajectories are compared to the business as usual case, which projects CO2 emissions to increase by 60% by 2050 compared to 2015. Results show that replacing all coal generation with renewables reduces CO2 emissions in 2050 by 8% compared to 2015, and that aggressive policy targeting the whole energy sector reduces CO2 emissions in 2050 by 40%. GAINS is used to show co-benefits and tradeoffs of each scenario, such as reductions in emissions control costs that accompany a switch to renewables. The approach provides supporting evidence for policies that exploit co-benefits and avoid contradictions by assessing multiple aspects of the energy sector within the integrated framework provided by the GAINS modeling platform

Co-benefits of post-2012 global GHG-mitigation policies

This report provides an analysis of the impact of global greenhouse gas policies on traditional air pollutants using the Greenhouse Gas and Air Pollution Interactions and Synergies (GAINS) model in the time horizon up to 2050. The integrated assessment framework of GAINS has been linked through an interface to the POLES global energy system model so that different global energy pathways can be implemented and examined. The impact analysis has been carried out based on projections of energy use data provided by the POLES model for two different climate policy scenarios, i.e., for a current policy Baseline scenario without any global greenhouse gas mitigation efforts, and a 2-degree Centigrade climate Mitigation scenario which assumes internationally coordinated action to mitigate climate change. Outcomes of the analysis are reported globally and for key world regions: EU-27, China, India and the US. The assessment takes into account current air pollution control legislation in each country. The results of scenario calculations for SO2, NOx and PM2.5 emissions, air pollution control costs, as well as health and environmental impacts, indicate significant scope for co-benefits made possible through climate policies. Climate mitigation measures appear to be more effective in reducing oxides of sulphur and nitrogen, while emissions of particulate matter are reduced to a smaller extent. Decarbonisation of the global energy system by 2050 results in SO2 and NOx emissions lower by two-thirds than in the world without GHG-abatement efforts. Corresponding reduction in the emissions of PM2.5 is estimated at about 30% relative to the Baseline and is particularly sensitive to the assumptions on projected biomass combustion. Expenditures on air pollution control under the global climate mitigation regime are reduced in 2050 by 250 billion Euros when compared to the Baseline scenario. Under the GAINS cost assumptions the largest potential for cost savings is reported for the transport sector, followed by savings in the power generation sector. Around one third of financial co-benefits estimated world-wide in this study by 2050 are allocated to China, while an annual cost saving of 35 billion Euros is estimated for the EU member countries if the current air pollution legislation and climate policies are adopted in parallel. This study also quantifies health impacts of air pollution in Europe, China and India in terms of loss of life expectancy related to the exposure from anthropogenic emissions of PM2.5, as well as in terms of premature mortality due to ground-level ozone. For example in China, current ambient concentrations of PM2.5 are responsible for 38 months-losses in the average life expectancy. In 2050, the global GHG-mitigating strategies reduce this indicator in China by 16 months. In addition, decrease of ozone concentrations in the three regions as estimated for the climate Mitigation scenario in 2050 might save nearly 80,000 cases of premature death per year. Similarly significant are reductions of impacts on ecosystems due to acidification and eutrophication

Factors determining recent changes of emissions of air pollutants in Europe

To support the European Commission in the review of the 2005 Thematic Strategy on Air Pollution, this report revisits the baseline scenario that was presented in 2005 in view of today's knowledge, in particular taking into account the impacts of the economic crisis on economic and energy development, and real-life experience with newly implemented emission regulations. It compares the final baseline emission projection developed in 2005 within the Clean Air For Europe (CAFE) programme for the Thematic Strategy on Air Pollution against the recent baseline projection prepared for the revision of the Thematic Strategy in 2012 (the TSAP-2012 baseline). The report reviews the assumptions on main drivers of emission changes, i.e., demographic trends, economic growth, changes in the energy intensity of GDP, switches to other fuels, and application of dedicated emission control measures. For most of these drivers, reality has developed rather different compared to what has been assumed in 2005. In reality, SO2 emissions in the old Member States in 2010 were 5% lower than what was projected by CAFE. NH3 was 10% and VOC 3% lower. NOx exceeded the CAFE projection by 7%, and PM2.5 by 10%. Larger differences occurred for the new Member States, where SO2 was 30% and NH3 16% below the levels suggest by CAFE. NOx was 11% higher, and PM2.5 and VOC 21% higher than estimated earlier. For 2020, the TSAP-2012 baseline projection expects for the EU-27 about 20% less SO2 emissions than the earlier CAFE baseline, with application of dedicated emission controls as the dominating factor for lower emissions. NOx would be 5-7% lower, depending on the assumptions on the effectiveness of the new vehicle emission standards. The PM projection is about 10% higher, while smaller differences emerge for VOC and NH3. Many of these changes are smaller than differences in the actual drivers. In many cases, higher effectiveness of dedicated emission controls compensated the lower than expected decline in total energy consumption as well as the delay in the phase-out of coal. A re-analysis of air pollution control costs based on the actual statistics suggests for 2010 6% higher costs earlier estimated, mainly due to higher consumption of coal that required more emission control efforts. For 2020, emissions of the new TSAP-2012 baseline (without additional measures) are substantially higher than the indicative targets for emission reductions established by the Thematic Strategy in 2005. As a consequence, the environmental targets established by the TSAP for the protection of human health, eutrophication and forest acidification would not be met by the TSAP-2012 baseline without additional measures