What are short-lived climate pollutants (SLCPs) and how do they affect climate change? Panelists on this webinar from WRI, Enhancing NDCs: Short-lived Climate Pollutants, make the case for why reducing SLCPs can give an immediate boost to lowering the global temperature while also decreasing local air pollution and improving human health.
The main SLCPs are black carbon, methane, hydrofluorocarbons, and tropospheric ozone. Black carbon is a leftover of incomplete combustion of fossil (oil, coal, natural gas) and wood fuels. Because air pollution standards in North America and Europe have decreased these emissions significantly, the majority of black carbon currently comes from Asia, Africa, and Latin America, mostly from household cooking and heating and transportation. Black carbon lives in the atmosphere for less than 12 days (vs. CO2 lingering for a century), but has a high global warming potential. Methane comes primarily from agriculture (livestock and rice cultivation), coal mining and oil and gas production (gas flaring), and waste management (landfills). Methane lives in the atmosphere for only 12 years, but is more than 80x more powerful at warming the atmosphere than CO2. Hydrofluorocarbons (HFCs) are industrial chemicals used in air conditioning and refrigeration that remain in the atmosphere for 15-29 years and are more than 1000x more powerful than CO2. They are quickly increasing, having been created to take the place of other cooling chemicals that were banned because they deplete the stratospheric ozone layer. Tropospheric (ground level) ozone, a secondary gas that results when sunlight interacts with hydrocarbons (like methane) and nitrogen oxide (NOx), lives in the atmosphere for just a few weeks.
Taken together, eliminating these SLCPs has the potential to reduce warming by .6 degrees in a short period of time. Given that these pollutants also foul local air quality and cause lung and heart disease, they have the potential to build local and immediate political will that can produce global and longer term benefits. Hence the strategy of specifically including actions to reduce and eliminate SLCPs in the Nationally Determined Contributions (NDCs) required under the Paris Agreement. The first round of NDCs submitted in 2015 and 2016 did little on SLCP mitigation. With revised NDCs expected this year and the focus on closing the emissions gap by 2030, there is a full court press to include SLCPs this time around.
The Climate and Clean Air Coalition (CCIC) is an alliance of 69 countries, 18 IGOs, and 60 NGOs focused on how SLCPs contribute to both global warming and air pollution. Its work with developing countries in particular highlights the opportunity for short-term reductions to have immediate impact on atmospheric warming and local air-borne illnesses. CCIC also stresses the impact on local food security because of SLCPs’ impact on agriculture production. The bottom line, says CCIC, is that
there is no way to the Paris goal without addressing SLCPs.
The webinar panelists describe several approaches to revising NDCs that include SLCP mitigation with other greenhouse gas emission targets. They include:
- incorporating analysis of local air pollution into national climate change analysis, using the data collection and analytical methodology and tools developed under the UNFCCC;
- approaching emission reductions by sector, because high CO2 producing sectors usually align with high SLCP production;
- focusing on key high emission sectors, like energy and transport; and
- aligning NDC targets with other environmental and sustainability goals, like decreased air pollution under national laws and HFC reductions under the Kigali Amendment to the ozone treaty
Ongoing NDC revision in Mongolia, Nigeria, and Cote d’Ivoire were featured in the webinar. Mongolia’s Prime Minister declared the country’s air pollution an economic development challenge in its Sustainable Development Goal review. The eight sectoral mitigation contributions in its revised NDC targets an overall 23% GHG reduction and is built on the country’s current air pollution reduction strategy. Nigeria’s NDC revision focuses on the priority sectors of energy (oil and gas), agriculture, industry, and transport, and is linking some 35 donors to support individual targets. Cote d’Ivoire has worked five years to integrate SLCPs into national planning, mapping key sectors where they are produced (household energy, transport, waste, agriculture, oil and gas production), and now establishing baselines and reduction measures for inclusion in their 2020 NDC revision.