1. SLCP and other air pollutants: an introduction for policy makers Jun-ichi Kurokawa Asia Center for Air Pollution Research (ACAP), Niigata, Japan High Level Sub-regional Consultation on Advancing Action on Short-Lived Climate Pollutants (SLCPs) In Southeast and Northeast Asia 19 Aug 2014, Bangkok, Thailand

2. Background Regional shares of global anthropogenic emissions of NO x and CO 2 in 2008 (EDGAR 4.2 for NO x ; CDIAC for CO 2 ) Emissions of air pollutants and green house gases in East Asia covering Northeast and Southeast Asia have already exceeded those in European and North American continent. This situation brings about not only serious urban and regional air pollution, but also prompted concerns on emissions in East Asia from the view of global climate change. NO x CO2CO2

3. What are Short-Lived Climate Pollutants (SLCPs)? UNEP & WMO (2011) Reduction of CO 2 emissions does not help to mitigate climate change until 2050. Reduction of emissions of BC and CH 4 will bring a relatively rapid climate response. Decrease of SLCPs coupled with CO 2 could lead to both the mid-term (2030-50) mitigation of climate change and the 2 ℃ capping in 2100. Major SLCPsLifetime Black Carbon (BC)Days Methane (CH 4 )12 years Hydrofluorocarbons (HFCs)15 years Tropospheric Ozone (O 3 )Weeks Long-lived Climate Pollutants (LLCPs) CO 2 : 60% 1000 yr SLCPs are agents which have relatively short lifetime in the atmosphere and have a warming influence on climate.

4. Black Carbon (BC)  BC is a tiny black particle and major component of PM 2.5, which has adverse effects on human health and ecosystems.  BC has a strong warming effect both in the atmosphere and on ice and snow. CCAC (2014) As a warming agent: Absorbing solar radiation and converting it to heat Increasing the melting rate of ice and snow As an air pollutant: Leading environmental cause of poor health and premature death such as cardiovascular mortality. Affecting ecosystem health.

5. BC emissions Comparison between anthropogenic and open biomass burning emissions in SE Asia Residential combustion is major emissions source in East Asia. Contribution from industry sector (coal combustion, production of cokes and bricks, etc.) is also large in China. Majority of emissions in transport sector is from diesel vehicles. Open biomass burning is important especially in Southeast Asia. [Tg/year] Global (GAINS) in 2005 China (REAS 2.1) in 2008 SE Asia (REAS 2.1) in 2008 Sector share of anthropogenic emissions * in Global total, China, and SE Asia Trends of anthropogenic emissions in China and SE Asia (REAS 2.1) [Tg/year] * Open biomass burning emissions are not included in these graphs.

6. Methane (CH 4 )  CH 4 is over 20 times more potent than CO 2 as GHGs.  CH 4 has indirect impacts on human health and ecosystems through its role as the primary precursor of tropospheric O 3. Major emission sources are agriculture, fossil fuel production and distribution, and waste treatment. In China, coal mining is the largest source. Oil and gas production and distribution as well as agricultural activities are estimated to be important emissions source in SE Asia. China (REAS 2.1) Southeast Asia (REAS 2.1) F_ = Fugitive emissions Global (EDGARv4.2) Sector share of anthropogenic emissions of Global total, China, and SE Asia in 2008

7. Hydrofluorocarbons (HFCs)  HFCs are man-made fluorinated GHGs.  There is no impact on human health and ecosystem.  HFC-134a has 1430 times more damaging influence on the climate system than CO 2. China 70% Japan 25% HFCs emissions in 2008 EDGARv4.2 Global Consumption by sector in 2010 CCAC (2014) HFCs currently represent only a small fraction of the total GHGs, but emissions of high-global warming potential (GWP) HFCs are rising very quickly. A recent study concluded that replacing high-GWP with low-GWP alternatives could avoid 0.1 ℃ of warming by 2050.

8. Tropospheric Ozone (O 3 )  O 3 is a secondary gas (not directly emitted).  Tropospheric O 3 is formed by sunlight-driven oxidation of precursor gases (CH 4, CO, NMVOCs, and NO x ).  Tropospheric O 3 is the 3 rd most important contributor to the human enhancement of the GHGs effects.  Tropospheric O 3 is a harmful air pollutant adversely affecting public and ecosystem health.  O 3 can make a transboundary air pollution problem. Differences as O 3 precursors: CH 4 and CO is important for tropospheric O 3 in global scale. NO x and NMVOCs is more effective for high surface O 3. CCAC (2014)

9. Adverse impacts of O 3  Regional and urban ozone pollution in East Asia is more serious than in Europe and North America.  Social incentives for controlling air pollution of O 3 as well as PM 2.5 are expected to be stronger in East Asia. Regional ratios of respiratory mortality (persons) related to O 3 in 2005 (Lelieveld et al., ACP, 2013) CCAC (2014) Majority of mortality related to O 3 is clearly in Asian region, especially China and India.

10.  Reduction of CH 4 is effective for long-term decrease of tropospheric (global) O 3.  For immediate reduction of urban/regional surface O 3, controlling NO x /NMVOCs is needed.  Both of NO x /NMVOC and CH 4 reduction are important and should be considered in East Asia especially in heavily polluted areas. Tropospheric O 3 and Surface O 3 -20% NO x -20% CH 4 -20% NO x /NMVOCs/CO Only reduction of NO x will lead to increase of CH 4, which increase net radiative forcing. However, if NMVOCs and CO are reduced at the same time with NO x, O 3 will be decreased without increase of net radiative forcing. (Fry et al., JGR, 2012) EA: East Asia, EU: Europe and North Africa NA: North America, SA: South Asia Effects of reducing anthropogenic EMs on Radiative forcing Warming Cooling

11. NO x and NMVOCs emissions Sector share of NO x emissions in 2008 For China, majority NO x emissions is from power plants, and those from industry and transport are comparable. Road transport is major emission source in Southeast Asia. NMVOCs emissions from road vehicles and solvent and paint use have large contributions in China. Contributions from road vehicles as well as biofuel combustion are large in Southeast Asia. Global (EDGARv4.2) China (REAS 2.1) Southeast Asia (REAS 2.1) Global (EDGARv4.2) China (REAS 2.1) Southeast Asia (REAS 2.1) Sector share of NMVOCs emissions in 2008

12. Benefits in the case if control measures are implemented globally by 2030 For NE/SE Asia and Pacific Climate  Avoided warming up to 0.05 ℃ in 2050  Reduced disruption of weather patterns  Reduced rate of melting and sea-level rise Avoided warming will be twice of that in NA and Europe. Public Health  Avoided annual deaths of 2.4 mil. from outdoor air pollution by 2030  Additional benefits from reduced indoor pollution 37% of global benefits in 2030 Agriculture  Avoided annual loss of 52 mil. tonnes of crop yields per year by 2030 28% of global benefits in 2030 Benefits of Mitigating SLCPs UNEP and WMO (2011) identified 16 cost effective SLCPs control measures such as for cook stoves, diesel vehicles, coal mines, municipal waste, etc. CCAC (2014)

13. Summary For near-term mitigation of climate change, reduction of SLCPs that have relatively short lifetime in the atmosphere and have warming influence on climate such as BC, CH 4, HFCs, and O 3 is essential. SLCPs have adverse impacts on human health and ecosystem including agriculture (food security) as well as climate change. Emissions of SLCPs in East Asia covering Northeast and Southeast Asia have already exceeded or at least been comparable to those in European and North American continent. Social incentives for controlling air pollution of O 3 as well as PM 2.5 are expected to be stronger in East Asia. In East Asia, both of NO x /NMVOC and CH 4 reduction are important and should be considered especially in heavily polluted area. Benefits of SLCP control measures for East Asia are estimated to be larger than other regions.

14. Thank you for your attention!

15. CCAC (2014)