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CCAC assessments

Demonstrating the multiple benefits of integrated climate and clean air action

The availability of robust and policy-relevant science on short-lived climate pollutants played a critical role in the establishment of the Climate and Clean Air Coalition.

The recommendations in the Integrated Assessment of Black Carbon and Tropospheric Ozone, the report on Near-term Climate Protection and Clean Air Benefits, as well as the report, HFCs: A Critical Link in Protecting Climate and the Ozone Layer, form the basis for our work.

We continue to build upon existing assessments to generate targeted data and information on short-lived climate pollutant emissions, impacts, and mitigation opportunities. Our integrated assessments on these pollutants provide a framework for national action and regional cooperation on mitigation efforts.

Assessments are more than just a report. Developing an assessment involves engaging governments, local policymakers, scientists, technical experts, and other key stakeholders in a well-structured consultation process. Through this process, we aim to strengthen the synergies between existing science and policy initiatives and ultimately support ambitious national and regional action.

Global Methane Status Report 2025

The Global Methane Status Report shows that while significant progress has been made since the launch of the Global Methane Pledge, further efforts are required to align with the level of ambition and action needed to meet the Pledge.

The report shows that although methane emissions are still rising, projected 2030 emissions under current legislation are already lower than earlier forecasts due to a mix of national policies, sectoral regulations, and market shifts. However, the report warns that only full-scale implementation of proven and available control measures will close the gap to the Global Methane Pledge’s target of a 30% cut from 2020 levels by 2030.

Global Methane Assessment

The findings in this assessment are the result of modelling that uses five state-of-the art global composition-climate models to evaluate changes in the Earth’s climate system and surface ozone concentrations from reductions in methane emissions.

Results allow for rapid evaluation of impacts from methane emissions and the benefits from mitigation strategies to the climate and ground-level ozone formation and air quality, public health, agricultural and other development benefits. The assessment results are also available in a web-based decision support tool that allows users to input different methane emissions reduction goals to calculate the multiple benefits at a national level.

Integrated assessment of air pollution and climate change for sustainable development in Africa

This assessment is the result of a scientifically underpinned process aimed at catalysing and supporting transformative development in Africa. It examines the role that short-lived climate pollutants, greenhouse gases, and other polluting emissions play in sustainable development. It analyses strategies, policies, and measures to mitigate these pollutants while supporting development and human health and wellbeing in Africa as the continent adapts to climate change and pursues its sustainable development objectives over the next four decades.

The Assessment was written by a pan-Africa team with contributions from international scientists and experts, and has helped build a regional science to policy network.

Air pollution measures for Asia and the Pacific

This report aims to support efforts to address air pollution in Asia and the Pacific by providing options for tackling air pollution in the context of the SDGs. To this end, it brings together evidence of historical trends with future development perspectives and provides detailed analyses of past and future economic trends and their implications for ambient and indoor air pollution.

From there, the report identifies a detailed portfolio of 25 cost-effective measures for technological and policy interventions that would contribute to the achievement of the SDGs while delivering the greatest benefits for human health, crop yields, climate and the environment, as well as socio-economic development. The report provides a clear picture of the benefits to be gained by adopting the measures and offers some implementation guidance through real-life case studies.

Global Nitrous Oxide Assessment

Nitrous oxide, considered to be a super pollutant, is the third most important greenhouse gas and the most significant ozone-layer depleting substance emitted today. Its human-induced emissions, which primarily originate from the agricultural use of synthetic fertilisers and manure, are increasing faster than previously projected. This Assessment identifies abatement measures available today that could reduce these emissions by more than 40 per cent below current levels.

Clean Air and Climate Solutions for ASEAN

Air pollution is a critical environmental challenge in Southeast Asia, affecting millions of lives. This report outlines a strategic approach to improving air quality while also combatting climate change in the ASEAN region. The Clean Air Solutions for ASEAN report identifies 15 priority measures that could more than triple the number of people breathing clean air by 2030 and reduce PM2.5 levels by 50–70%. These solutions also provide significant climate benefits, cutting emissions of black carbon (-70%), methane (-39%), and HFCs (-75%), alongside a 25% reduction in CO₂ emissions by 2030. Importantly, nearly 40% of the air pollution reduction potential can be achieved by strengthening enforcement of existing policies, highlighting the need for better implementation rather than entirely new regulations. This report is a roadmap and call to action for ASEAN nations, urging policymakers, businesses, and communities to adopt science-based solutions for a healthier, more sustainable future.