United Nations Environment Programme

Tackling short-lived climate pollutants

The Paris Agreement must enable countries and cities to combat air pollution and climate change simultaneously
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Combined air pollution and climate policies multiply benefits, make them direct and immediate, and are the best pathway to a clean climate and healthy economy.

Since 2014, Chile’s Ministry of Environment has focused on three objectives: identifying and addressing the climate effects of air pollution; taking a leading role on addressing short-lived climate pollutants (SLCPs); and working to integrate these two concepts at both the local and global level.

One of the greatest challenges that we face in achieving our environmental, development, and climate goals is identifying metrics that can harmonize our near- and long-term objectives and identify win-win solutions that help us achieve both together.

Yet science tells us that simultaneously addressing drivers of both near-and long-term climate change is the only way to realistically achieve our climate and development goals. Indeed, being able to do both at the same time brings much greater benefits than either can separately, particularly for public health and air quality.

This made us realise that we must include measures to reduce SLCPs, particularly black carbon. Informed by the Climate and Clean Air Coalition draft guidelines, the Intended Nationally Determined Contribution (INDC) that we submitted ahead of the Paris Agreement recognized that taking action on SLCPs can provide a “substantial contribution to the mitigation of the causes of climate change,” while also providing co-benefits such as “reducing the levels of local atmospheric pollution in urban centers.” We joined Mexico and Nigeria in noting the important contribution of black carbon to fine particulate matter air pollution and climate change in our INDCs.
We are already turning our pledges into action. We are implementing local decontamination plans focused on black carbon in numerous cities throughout Chile. These include measures such as: subsidies to improve insulation in 300,000 homes and overhaul 400,000 dirty wood burning stoves and heaters; banning the use of firewood in the urban area of Santiago; modernizing the Transantiago bus fleet to Euro 6 emissions standard, and setting stringent emissions standards for industrial, transport, and residential sectors. We are also establishing a permanent ban on non-Euro 5 diesel vehicles, hoping to achieve a deep overhaul of our car fleet. Finally, we are the first country in Latin America to regulate existing and new off road machinery.

We have designed this new Santiago Respira plan with the hope of reducing wintertime pollution by 80 per cent, and thus reducing premature mortality by 2,200 cases per year. These measures come at a cost, but the benefits are eightfold, due to fuel savings and health benefits. Through these actions we are proving that it is possible for countries to improve the quality of life of their citizens while also being responsible global citizens. However, we continue to struggle to define and communicate our multiple objectives within the context of the climate treaty and sustainable development.

If we are to understand the implications of our mitigation actions and pledges on local and global temperatures in the near and long term, and be able to quantify benefits from improved air quality, we need to understand what the pledges mean for different substances emitted to the atmosphere. It would be an important step, therefore, for the Ad Hoc Working Group of the Paris Agreement (APA) to recommend that countries pledge emission reduction targets of each substance separately as part of their Nationally Determined Contributions (NDCs), instead of combining them into a single carbon dioxide equivalent (CO2e) pledge.

The use of a single metric obscures crucial differences between substances: how they act in the atmosphere, how long they stay there, and what other effects they have beyond warming such as the impacts of these pollutants on near-term health and agriculture. The use of a single combined pledge is a significant barrier to reaching the goals of the Paris Agreement of keeping warming “well below 2°C” above pre-industrial levels while also recognizing the “intrinsic relationship that climate change actions, responses, and impacts have with equitable access to sustainable development and eradication of poverty.”

As the APA considers the formal methodology for future NDCs it can build upon the strength of the INDCs by allowing Parties to: pledge emission reductions of substances individually (e.g. as tons of each substance) rather than in CO2e; report on progress made in implementing and achieving their NDCs substance by substance; and voluntarily include pledges for non-greenhouse gas emissions, including aerosols such as black carbon, that affect the climate, health, and ecosystems.
Taking this approach would provide clear, unambiguous data for the United Nations Framework Convention on Climate Change to track progress towards global climate goals while also recognizing the distinct multiple benefits of SLCP strategies. It would make the system more precise and transparent, and would facilitate a more holistic approach to climate action, aligning closely with social, economic, and environmental priorities. This would also allow countries like Chile to focus on climate and development benefits of particular concern to them, such as decontaminating cities, protecting glaciers and areas with snow cover, protecting water supplies, agricultural and wine activities; and above all, the health of the people.

Allowing countries to set separate pledges for different emitted substances would send a powerful message that countries need not choose between their near-term sustainable development priorities and long-term climate goals; they can and should achieve both. The overall objective of our climate negotiations is to protect the planet and ultimately save lives. We cannot overlook the fact that acting on SLCPs now saves lives now and protects our climate immediately. A shocking 92 per cent of the world population breathes dirty air. Nobody has overcome air pollution issues. Combined air pollution and climate policies multiply benefits, make them direct and immediate, and are the best pathway to a clean climate and healthy economy. Many have focused first on air pollution, and then climate. But working on both could be the most efficient, cost-effective, and successful approach.