5.5 Response: policies and governance

A wide variety of governance approaches and policy instruments have been used to help mitigate the sources and impacts of air pollution, climate change, stratospheric O3 depletion and PBTs, including the following.

The effectiveness of specific examples of these policies is explored further in Chapter 12.

Different governance approaches have been adopted at local, provincial, country and international scales depending on the specific institutional, economic, technological and political contexts. Often multiple complementary approaches are deployed simultaneously to address a single issue or source. Different mixes of approaches may be used to address similar issues, even in a single jurisdiction.

Table 5.2: Global environmental agreements relevant to climate change, stratospheric O3 depletion and PBTs
Climate change
  • 1992 United Nations Framework Convention on Climate Change (UNFCCC)
  • 1997 Kyoto Protocol
    • 2012 Doha Amendment
  • 2016 Paris Agreement
Stratospheric O3 depletion
  • 1985 Vienna Convention for the Protection of the Ozone Layer
  • 1987 Montreal Protocol on Substances that Deplete the Ozone Layer
    • 1990 London Amendment
    • 1992 Copenhagen Amendment
    • 1997 Montreal Amendment
    • 1999 Beijing Amendment
    • 2016 Kigali Amendment
Persistent bioaccumulative toxic chemicals (e.g. POPs and Hg)
  • 1989 Basel Convention on the Control of Transboundary Movements of Hazardous Wastes and their Disposal
  • 1998 Rotterdam Convention on the Prior Informed Consent Procedure for Certain Hazardous Chemicals and Pesticides in International Trade
  • 2001 Stockholm Convention on Persistent Organic Pollutants
  • 2013 Minamata Convention on Mercury

The existence and extent of implementation of air-related policies also vary widely based on differences in institutional capacity and culture in different regions of the world and at different spatial scales. In some regions, such as North America and Europe, there are well-developed, federated systems of national, provincial and local policies and enforcement programmes designed to achieve common policy objectives. In other regions, international agreements or national legislation may exist, but implementation and enforcement are weak due to a lack of institutional capacity at the national or subnational scale. In some regions, city governments are developing the primary policy response to these issues, with simultaneous benefits for other parts of their countries.

Climate change, stratospheric O3 depletion and PBTs have been recognized as shared global problems. Table 5.2 lists some global environmental agreements that have been developed to motivate, enable and coordinate ongoing efforts to address these challenges. These set out common objectives and obligations, which are implemented through different policies developed at national to local levels. One of the most successful global agreements is the Vienna Convention and Montreal Protocol to address stratospheric O3 depletion, which in 2009 became the first United Nations convention to be ratified by all United Nations member states. The most recent amendment to the Montreal Protocol, the 2016 Kigali Amendment, is designed to limit the impact of ODS substitutes on climate change.

Adopted in 1992, the United Nations Framework Convention on Climate Change (UNFCCC) has led to the negotiation of a series of protocols and agreements on “common but differentiated responsibilities” to address GHG emissions (United Nations 1992). The UNFCCC divides countries into developed (Annex I) and developing countries. This differentiation has been key to the design of mechanisms to transfer between countries the technology and resources needed to mitigate emissions (including Activities Implemented Jointly, Clean Development Mechanism and Joint Implementation). Under the Kyoto Protocol and Doha Amendment, Annex I countries agreed to specific emission reduction commitments. The second commitment period (2013-2020) of the 1997 Kyoto Protocol has yet to be approved by a quorum of 144 nations. The 2015 Paris Agreement set the goal of limiting the global average temperature increase to well below 2°C above pre-industrial levels by 2100, with ambition to limit the increase to less than 1.5°C. All countries are required to present periodically to the Convention Secretariat national GHG inventories and Nationally Determined Contributions (NDCs), or emission reduction commitments. To achieve the 1.5°C goal, GHG emissions need to be decreased significantly in the coming years and be brought to net zero by around mid-century (see Chapters 21 and 22). Studies have suggested that there is a greater than 90 per cent chance of exceeding 2°C warming under the current pledges submitted by national governments, which achieve only a third of the mitigation required to be on a least cost path to stay below that threshold. However, pathways towards staying below 1.5°C and 2°C are still technically feasible (Xu and Ramanathan 2017).

Figure 5.16: Map of groupings of selected regional multilateral air pollution agreements

Although air pollution travels around the world, there is no single global agreement addressing air pollution; rather there is a patchwork of regional intergovernmental agreements (Figure 5.16). In general, this patchwork has good geographic coverage, but is uneven in terms of the coverage of pollutants, sources and capabilities. Furthermore, this patchwork does not encourage the transfer of experience and resources from richer to poorer countries. The oldest and most-developed among these is the 1979 Convention on Long-Range Transboundary Air Pollution (CLRTAP) organized under the United Nations Economic Commission for Europe (Sliggers and Kakebeeke eds. 2004; Maas and Grennfelt eds. 2016). In the Russian Federation and Central Asia, the CLRTAP overlaps with the grouping of agreements under the umbrella of the Asia and the Pacific Clean Air Partnership. There are three regional agreements on air pollution in Africa which overlap each other and have a few members in common with the Council of Arab Ministers Responsible for the Environment.

To guide their air pollution policies, many countries have developed national ambient air quality standards, or guidelines for a number of common pollutants (Kutlar Joss et al. 2017). These can differ with respect to the pollutant targeted, concentration level, averaging time, frequency of occurrence and measurement protocols, making comparisons of stringency difficult. In 2005, a WHO expert panel developed a set of air quality guidelines that are intended to be globally applicable for general population exposure and a set of recommended interim targets for some pollutants for areas that exceed the guidelines (WHO 2006; see Table 5.3). The interim targets were suggested for use by highly polluted areas as incremental steps towards achieving the guideline values. Each interim target is associated with a specified decrease in mortality risk (WHO 2006).

Table 5.3: WHO Air Quality Guidelines and Interim Targets
Pollutant Averaging time Unit Interim targets Air quality
1 2 3 Guideline
PM10 Annual μg/m3 70 50 30 20
24 hours μg/m3 150 100 75 50
PM2.5 Annual μg/m3 35 25 15 10
24 hours μg/m3 75 50 37.5 25
NO2 Annual μg/m3 - - - 40
1 hour μg/m3 - - - 200
SO2 24 hours μg/m3 125 50 - 20
O3 8 hours μg/m3 160 - - 100
CO 1 hour mg/m3 - - - 30

The ability of governments and the public to compare air quality monitoring data to such guidelines and standards and associated information about health benefits has been important in developing awareness and motivating mitigation. Thus, improving air quality monitoring infrastructure and the use of air quality and health effects information in benefit-cost analyses of mitigation measures were identified as priorities in the GEO-6 regional assessments.

Box 5.1: UNEA 3/8 Resolution
Preventing and Reducing Air Pollution to Improve Air Quality Globally

The resolution urges Member States to:
  • Take action to decrease all forms of air pollution
  • Establish systems to monitor air quality and emissions
  • Set ambitious air quality standards
  • Address short lived climate pollutants as part of national action plans
  • Integrate air pollution management into national development planning
  • Create awareness of air pollution costs and benefits of air pollution control
  • Strengthen national and sub-national capacity for air quality management
In addition, it calls for strengthened cooperation to address air pollution at the local, national, regional and global levels. The resolution also requests UN Environment to undertake additional technical support, capacity building and analysis to support Member States in improving air quality.

Significant successes have been achieved through national and international policy and regulatory structures that have been developed over recent decades, as evidenced by the declining trends in emissions and increasing trends in activity and production (see Section 5.2). However, past policy responses may not be well suited to addressing the problems and sources that remain or that are emerging, particularly in the near term. Particularly if government capacity or regulatory structures are lacking, responses that engage a broad mix of stakeholders to integrate air-related concerns into broader policy and investment decisions (e.g. transportation planning, land-use planning, economic development investments, behavioural change) may be more capable of addressing diffuse sources of emissions and promoting innovation. Cities have been important centres of policy innovation and policy integration and continue to provide important opportunities for progress. The non-governmental organization Clean Air Asia is a leading example of efforts in this arena, bringing together city governments, national ministries, industry and other stakeholder groups from more than 1,000 cities across Asia to share lessons in developing air pollution, climate change, transportation, land-use and energy policies (Clean Air Asia 2017). The C40 Cities Climate Leadership Group is another example, which connects officials in cities to their peers in cities around the world to exchange information as they face common challenges associated with climate change mitigation and adaptation (Day et al. 2018).

At both international and local levels, coalitions and initiatives have formed between governments, industry and other groups to facilitate specific actions. The Climate and Clean Air Coalition for Reduction of Short-Lived Climate Pollutants (CCAC) is an example of a coordinated effort to make nearterm progress focused on specific pollutants and sectors (CCAC 2015).