Atmospheric Pollution: Developing a Global Approach

Transcription

1 Discussion Paper # 1 Atmospheric Pollution: Developing a Global Approach Prior to the 1970s atmospheric pollution was considered to be a local, urban, problem that was best tackled through national or local initiatives. As scientific knowledge increased, it became clear that emissions to the atmosphere were also leading to significant transboundary problems through the long-range transport of pollutants. Such regional impacts of sulphur and nitrogen compounds were clearly problems which no one country could tackle on its own. It is now clear that transboundary pollution is an important issue in all parts of the globe and some pollutants are travelling hemispherically and globally with issues such as the Atmospheric Brown Cloud coming to the fore. The transfer of pollutants across the Northern Hemisphere, especially of tropospheric ozone, is now a significant issue affecting the ability of regions to tackle the pollution problems through activities within their region alone. Carbon monoxide from biomass burning is an issue across the Southern Hemisphere. In addition, there are an increasing number of atmospheric pollutant problems that have a global dimension such as the transfer of persistent organic pollutants (POPs) and mercury and interactions with global climate balance through the increase in aerosol concentrations in the atmosphere leading to a global dimming. The emission, transport and transformation, and deposition of long-range transboundary air pollution is having dramatic impacts on human health and well-being, economies, livelihoods, ecosystem integrity and productivity in all parts of the globe. The question is: how can we develop systems that can comprehensively tackle these emerging issues? The Global Atmospheric Pollution Forum was established to encourage wider debate and innovative solutions to the challenges of air pollution at the regional, hemispheric and global scales. This summary discussion document derives from a series of inter-regional dialogues for scientists and administrators held during It is a working document intended to elicit views and suggestions. The Issues Air pollution continues to cause the premature deaths of a large number of people across the globe, particularly in urban centres. WHO estimates that around 800,000 advanced deaths per year are being caused by outdoor air pollution, mainly through the action of particulate matter. Although the air quality of some cities has improved dramatically over previous decades in the richer nations, the air quality of many developing nation cities has deteriorated and is extremely poor in many countries. This is now a shared problem of global dimensions. Regional air pollution problems are related to those pollutants that are transported over large distances such as sulphates, nitrates, ammonium, small particulate matter (e.g. PM particulate matter with a diameter of less than 2.5 micro-metres) and ground-level ozone. The first transboundary problem to be identified was the acidification of lakes in Scandinavia and subsequent forest damage in central Europe. Although the acidifying deposition has been reduced in the countries of Europe and North America, with some recovery seen in lakes, acidification is still present. Now the fear that these problems may be being replicated in other parts of the World has caused acidification to become an increasing focus in parts of Asia where there is a combination of high deposition and ecosystem sensitivity. Other regional problems have subsequently emerged. Nitrogen deposition is a threat to biodiversity over large parts of Europe. Recent calculations have shown that many parts of the World, including some of the World s most important biodiversity hotspots, are receiving 1

2 nitrogen deposition in excess of 10 kg N per hectare per year which is a level that has drastically altered sensitive plant communities in Europe. Tropospheric (ground-level) ozone is now known to be a very important regional pollutant causing damage to health, materials and crop yield and quality. In contrast to pollutants causing acidification, the ozone situation has not much improved in Europe and background concentrations are rising. Initial results confirm that this is already an important pollutant in developing country regions and is predicted to increase as a problem. The rising background in Europe reflects a rising background concentration throughout the Northern Hemisphere which is being caused by the combined emissions of the precursors of ozone formation (NOx and volatile organic compounds - VOCs) from all regions in the hemisphere. Recent evidence shows that, once formed, the ozone can be transported far between regions and across the whole northern hemisphere. The aerosol burden to the upper atmosphere is leading to the widespread dispersal across and between continents. There has recently been a focus on the Atmospheric Brown Cloud in Asia and the River of Smoke in southern Africa as well as the transfer of soil dust between the Sahara and the Americas. The impacts of these Brown Clouds include changes to the patterns of rainfall over large areas and there are fears that this could exacerbate water availability problems in drought-prone regions. Other important effects are the significant reduction in sunlight reaching the ground, the implications of which are not fully known, and the cooling effect of the aerosols in the clouds that counters the warming effect of the climate change. The widespread nature of the pollutants in the atmosphere has led to the notion that there is a general Greying of the northern hemisphere and the phrase global dimming, referring to the sunlight reduction, has been coined to emphasise the global nature of this problem. This reflects the view that pollution problems are moving from the regional through to global scale. There are some pollutants whose transport is truly global in nature including POPs and mercury. These move by various atmospheric processes and through various media and tend to accumulate in food chains. There seem to be particular risks from POPs to animals higher in food chains, especially in Arctic and Antarctic regions, although the full extent of the impact is not fully understood. The increasing relevance of larger spatial scales, revealed as scientific knowledge has progressed, is indicated in Figure 1. Figure 1 Evolution of the perceived scale of air pollution problems. Points indicate approximately when scientific consensus emerged and public policy action should be considered. Some pollutants such as ozone and particulates (first Total Suspended Particles (TSP), then PM 10 and then PM 2.5 ) have been reassessed over time as relevant on larger spatial scales (from Keating, T.J, West, J.J and Farell, A.E Prospects for international management of intercontinental air pollution transport. In Inter-Continental Transport of Air Pollution ed by A. Stohl. The Handbook of Environmental Chemistry 4. Springer-Verlag, Berlin). 2

3 Other well-known global atmospheric problems result from emissions of ozone depleting substances to the atmosphere causing stratospheric ozone depletion and the creation of the ozone holes over the Antarctic and Arctic, and climate change caused by emissions of greenhouse gases. Regional, Hemispheric and Global Initiatives Tackling Air Pollution Air pollution has traditionally been tackled at urban, national and regional scales, depending on the particular problems and policy processes. Regional cooperation was initiated in the 1970s with the formation of the Convention on Long-Range Transboundary Air Pollution under the United Nations Economic Commission for Europe (UN ECE) as it was recognised that nations could not deal with the issues on their own. As well as dealing with transboundary issues, the process of tackling air pollution at European scale has encouraged interest and capacity building across Europe for air pollution at all scales. The regional scale has therefore become established as an important scale at which to understand common and shared problems of air pollution and other regional initiatives have begun to emerge elsewhere the World to tackle a worsening air pollution situation. In Asia, countries in East and SE Asia have initiated scientific cooperation under EANET, the Acid Deposition Monitoring Network in East Asia. In South Asia, eight countries have formally agreed to cooperate under the implementation of the Malé Declaration on the Control and Prevention of Air Pollution in South Asia and its Likely Transboundary Effects. Countries of SE Asia have agreed a formal treaty on the control of haze pollution from forest clearance and the Central Asian Republics are becoming involved in the UN ECE Convention on LRTAP. The issue of the Atmospheric Brown Cloud (see Figure 2) is being studied across Asia under the ABC project. There is a network of Asian cities organised under the Clean Air Initiative (CAI-Asia) understanding and tackling air pollution at urban scales. Seven countries of southern Africa have initiated scientific activities under APINA, the Air Pollution Information Network for Africa. In Latin America IANABIS, the Inter-American Network for Atmospheric and Biospheric Studies, is preparing scientific and science-policy initiatives across South and Central America as well as in Mexico. Therefore, while there is now an extensive range of regional networks, there is no mechanism to help them share experience and identify opportunities for effective collaboration and thus speed the development of knowledge globally as a prerequisite for political action to reduce the pollution burden on people and ecosystems. Figure 2 Pollution haze over NE India and the Bay of Bengal (source: NASA) Although it remains essential that regional and subregional networks develop organically in ways which reflect their own circumstances, a more effective framework for co-operation is now required if further progress is to be made. There is no policy mechanism working at the hemispheric scale that can tackle the problems associated with hemispheric air pollution. A Task Force on Hemispheric Transport of Air Pollution (TF HTAP) has recently been set up under the Convention on LRTAP. It has a remit to explore scientific issues related to hemispheric pollution problems but this is the only activity at this scale thus far. 3

4 Within this framework a number of key priorities emerged, which, subject to the results of wider consultation, are likely to form the basis of the Forum s future programme: 1. There are now major opportunities for progress in air pollution abatement at the regional scale, but these depend on more effective inter-regional collaboration. This, in turn, is likely be the most effective way forward in securing progress at the hemispheric and global scales. Figure 3 Image of the River of Smoke event in Africa captured by the SeaWiFIS sensor onboard the OrbView-2 platform on 4 September 2000 (Source: NASA & CSIR) There is some activity at the global scale covering the problems of POPS and mercury. The Stockholm Convention has been set up to reduce or eliminate the dirty dozen POPs at global scale. There is no treaty for mercury but there are assessment activities being developed under UNEP. Although there is this limited degree of global activity there is no mechanism to deal with all of the up-and-coming global or hemispheric scale issues or that can treat common problems that have a global dimension. Regions and regional air pollution organisations - differ greatly in their physical, economic and political composition. However, more effective sharing of skills, scientific knowledge and policy experience amongst regions can avoid the repetition of mistakes, and save time and resources, as well as promoting the infrastructure required for action at the hemispheric and global scales. For the Forum this emphasises the importance of continuing its programme for fostering discussions and consensus building amongst regional networks, and widening its current programme of projects on technical collaboration from the current work on emission inventories and impacts to cover other areas of potential inter-regional co-operation. Opportunities for Progress In the light of this assessment, two overriding challenges emerged from discussion at the Inter- Regional Dialogues sponsored by the Forum. The first is the need to secure greater awareness of the problems and commitment to action - at civic, business and political levels. The second is to ensure that action to tackle regional, hemispheric and global air pollution is seen in the context of pollution at all scales, and in the context of wider social and economic development policies and in particular in terms of how far it can help developing countries reduce their local and regional pollution problems in a way which optimises sustainable development, whilst tackling the overall hemispheric and global pollution burden simultaneously. Figure 4 Sources of air pollution (modified from UNEP) 4

5 2. A comprehensive global atmospheric pollution convention is unlikely to be feasible for some time, but there are opportunities to build progressively on existing institutions. Current air pollution conventions generally address relatively narrow/specific purposes, but there may be scope to expand their membership or functions to help tackle the wider problems that have emerged since their establishment. This may prove a more simple and realistic course than seeking to establish new global conventions in the short term. The decision of the LRTAP Convention to examine the possibility of opening the Convention to signature by states outside the UNECE region is a welcome first step. Equally, it may be useful to explore how far treaties such as the Vienna and Stockholm Convention could be adapted to serve wider functions. required. There is a need and opportunity for early progress here. 4. Future initiatives could benefit in particular from the LRTAP Convention s Experience in air pollution abatement systems. The LRTAP Convention has already developed wide air pollution functions, and exceptionally, has a relatively long experience of experimentation with different policy systems for air pollution abatement - including emission ceilings, standard percentage emission reductions, Best Available Technology, and Integrated Assessment Modelling. Although its current systems may not prove appropriate for application at the hemispheric and global scales, or by regional networks elsewhere, its past experience does provide a valuable fund of knowledge on the operation and practical implication of different regulatory systems. In common with experience from elsewhere this needs to be systematically reviewed to assist future policy development in other regions and at the hemispheric and global scales. 5. In order to inform the global community of the state of the atmospheric environment there is a need to develop high quality databases of important information and promote a global information flow, assessment and capacity building programme. Figure 5 The inter-regional meeting held under the auspices of the Forum in Tokyo in 2005 between representatives from Europe, the USA and East Asia. 3. Globalization is creating both needs and opportunities for enhanced international cooperation in air pollution control particularly in respect of the rapid increase in the relatively uncontrolled aircraft and ship emissions. While for CO 2 aircraft emissions are most significant, for conventional pollutants shipping may prove the more significant. In the UNECE area, for instance, shipping accounts for an increasingly large proportion of SOx and NOx emissions. While present arrangements allow special controls in sensitive areas there is an increasing perception among those involved in the shipping industry that wider international standards and regulation are There is an opportunity for a more systematic development of monitoring, assessment and mitigation activities at global scale. Harmonization is required between the many existing databases and new activities should be initiated so that a global coverage can be obtained. These databases would then form the basis for any future policy action at global scale. Such a function might most naturally fall to UNEP. 6. Policy development should emphasize more strongly the relationship between air pollution and climate change. Air pollution and climate change both fundamentally the result of energy systems - are inextricably linked: it is now estimated, for instance, that ozone accounts for a significant proportion of radiative forcing. It is time for policy systems to recognise this more explicitly. 5

6 Whilst experience suggests that bringing together the international negotiating machinery for air pollution and climate change would unlikely to be beneficial in the short term and further delay effective action, policy development should increasingly converge in two areas: - Co-benefits- It is widely recognised that action on either air pollution or climate change can increasingly yield co-benefits for the other. Seldom therefore can policies at any level be sensibly considered in isolation from the other, and, increasingly, integrated strategies will be needed. - Particulates, Ozone and Global Dimming At the scientific level there is general consensus on a strong pollution/climate connection and the magnitude of radiative forcing of different particulate pollutants is relatively well known. Clearly, some issues need further work, such as the integrated ozone and sulphate aerosol effect and the importance of global dimming. These issues need to be clarified as a matter of priority as the costs of delaying action could be so great that policy judgements on the best available scientific assessment cannot be avoided for much longer. While scientific investment in the area has significantly increased, more needs urgently to be done. within the short term. The Forum s discussions suggested that these lie primarily in the field of further strengthening of regional air pollution networks, promoting co-operation and consensus among them, and encouraging best practice and the harmonization, where relevant, of technical systems. It is on this basis that it is proposed that the Forum, in the next two years, continue with its programme of inter-regional dialogues, and expand its current work on technical co-ordination currently focussed on harmonization of regional emission inventories to include parallel projects on critical areas for cooperation such as assessment of crop yields, health, materials and, other impacts, and abatement policy systems. This process should help bring together existing initiatives around the World to promote potential synergies and define areas where new innovative approaches are required. Next Steps The Forum s discussions recognised that securing the necessary progress on hemispheric and global air pollution is unlikely to be quick or easy. Most of the policy redevelopment priorities set out in the previous section will require co-operative action by a wide range of parties over a significant period. That makes it the more important to press ahead with those steps which are practical and realistic Santiago, Chile Figure 6 Smog in Santiago, Chile (source: Hector Jorquera) Please send comments and suggestions on any aspect of this paper to: Kevin Hicks at the Forum s Technical Secretariat: khicks@york.ac.uk 6