Air pollution and climate change are closely linked. Short-lived climate pollutants are the most important contributors to climate change after carbon dioxide, and also contribute to negative impacts on human health, and on important crops like wheat and soybeans.
So it makes sense to address air pollution and climate change together – and doing so provides opportunities to enhance countries’ climate action plans through their Nationally Determined Contributions (NDCs). In particular, we identify four such opportunities.
1. Reduce methane and hydrofluorocarbon emissions
Methane is a greenhouse gas that also contributes to the formation of ozone – an air pollutant that affects human health and damages crops. Less methane in the atmosphere means better air quality and fewer greenhouse gases.
To reduce methane, the oil and gas sector can minimize venting; the waste sector can minimize emissions from solid waste at landfills; and the agriculture sector can reduce emissions from rice production – to name a few options.
Next we have hydrofluorocarbons (HFCs), a group of industrial chemicals primarily used for cooling and refrigeration. HFCs are not abundant in the atmosphere right now, but have one of the highest emission rates of all the greenhouse gases. If we phased down their emissions (as countries have agreed to do in the Kigali Amendment to the Montreal Protocol), we could avoid up to 0.5 degrees of warming by 2100.
Emissions can be reduced by replacing HFCs with other refrigerants, like hydrocarbons or ammonia; or by improving insulation and building designs to reduce our reliance on air conditioners.
2. Reduce black carbon emissions
Black carbon is a short-lived climate pollutant that warms the atmosphere by absorbing radiation. Deposits are also found on top of snow and ice, which darkens Earth’s surface and reduces how much sunlight is reflected back to space – ultimately leading to higher temperatures.
Black carbon is also a component of PM2.5 particulate matter, which can penetrate the lung barrier and enter the blood system, contributing to diseases like heart disease, strokes and lung cancer.
Actions to reduce black carbon emissions include introducing more stringent vehicle emission standards for diesel vehicles; adopting more efficient fuels and technologies for cooking and heating; and eliminating open burning of agricultural waste.
In almost all cases, these actions also reduce emissions of other air pollutants that contribute to PM2.5 formation – and may also reduce CO2 emissions. Reducing black carbon emissions therefore has an amplified positive impact on our health and environment.
3. Focus on actions that reduce CO2 while tackling air pollution
Actions to reduce greenhouse gases can also reduce air pollution: like by switching to renewables and improving energy efficiency across industrial, residential and commercial sectors.
On a policy level, by highlighting and prioritizing mitigation actions based on cleaner air and associated with crucial Sustainable Development Goals, we can build a broader coalition of stakeholders who see the value in following through on these measures. This increases the likelihood of implementation.
“If the NDC reflects all the actions set out in a country’s different plans and strategies, that can make the NDC document become more ambitious – without the country having to do any more work than already planned.”
4. Make sure NDCs reflect all planned actions to reduce emissions
Many countries have emission reduction plans outside of formal climate change planning processes. These can include air pollution strategies, national development plans, or strategies for sectors such as transport, energy or waste. Different groups develop these plans and strategies at the same time, but they are not necessarily aligned.
But all these plans could contain steps that will affect emissions. By looking at the different plans and making sure the country’s NDC reflects the actions set out in each and every one of them, that NDC document can become more ambitious – without the country having to do any more work than already planned.
For instance, it might be that the government has put forth in its NDC that it wants to introduce a vehicle emissions standard. It would then be worth looking across ministries to find other plans to introduce an even more stringent standard, perhaps in a bid to reduce black carbon emissions and improve public health. That ambition could then be reflected in the NDC, making it more ambitious.
Integrated action requires integrated planning
While there are obvious benefits in a joined-up approach on reducing greenhouse gas emissions and air pollutants, it does require integrated planning on an institutional and practical level.
Currently, most governments have different departments dealing with the issues of climate change and air pollution, and institutional barriers may be considerable. But it is possible to reduce these barriers.
SEI has been working with Côte d’Ivoire officials in charge of air quality, using our LEAP-IBC tool to look at greenhouse gases and short-lived climate pollutants together. This work spurred interest and led to greater cooperation across institutions.
The course of action for more integrated planning can be broken down into seven steps.
- Develop an emissions inventory for both short-lived climate pollutants and greenhouse gases. These inventories are usually prepared separately, but it’s more efficient to develop them jointly – much of the required data is actually the same. The additional work needed to integrate them is less than the effort to construct separate inventories.
- Create projections for how emissions are likely to increase in the future, given – for example – population growth. In many low- and middle-income developing economies, populations are expected to grow substantially; therefore increasing emissions. It is also important to model how different sources of emissions will change over time.
- Recognize that countries already have policies and plans that will affect emissions in different sectors. There may be policies, plans and strategies within agriculture, energy, air quality, transport. It’s important to understand to what extent implementing all these plans will allow a country to achieve its climate change and air pollution goals.
- Review what additional policies and measures could be taken in different sectors that existing plans have not considered, such as those highlighted in international assessments.
- Quantify how these measures will reduce the emissions of greenhouse gases and short-lived climate pollutants.
- Quantify the multiple benefits of implementing these measures. One question that can be answered is: what is the effect on the levels of air pollution that people are exposed to, and what health benefits result from that? The reason for extending analysis to the impact is that it takes to the level people care about. This can be used also to prioritize emissions reduction and pick mitigation measures that maximize whichever benefits policy-makers are most interested in.
- The final step is to select a package of measures that will achieve both climate change mitigation goals and air pollution reductions, based on the above assessment.
Better NDCs, better development
Taking these steps produces more transparent action plans and helps in identifying co-benefits with development goals.
The NDC Explorer – a platform developed by SEI and the German Development Institute DIE – shows that current NDCs are not clear in how mitigation will be achieved.
In the first round of NDCs, countries tended to set a target without detailed analysis on how to achieve it. Specifying mitigation measures in the NDC increases transparency and increasing the likelihood that the measures will actually be put in place.
Looking at the level of individual measures has another advantage: identifying co-benefits with other development goals. One country may consider modernizing its bus fleet, for instance, with a choice between electric buses and those that run on natural gas. Both options are good in reducing air pollution – but only electric buses charged with low-carbon electricity also serves to reduce greenhouse gas emissions.
Win-win for developing countries
Developing countries tend to prioritize development over climate change mitigation, which is understandable. The great majority of developing nations produce relatively little greenhouse gas emissions; and have limited resources to provide food and clean water to their citizens, build safer cities, or provide access to electricity.
But planning integrated action on air pollution and climate change does not cost much more than planning each issue separately. It also opens up opportunities to advance development by reducing air pollution and enables more ambitious NDCs: a win-win approach.