Global Air Pollution: Science and Implications Outline by Dan Jaffe, UW-Bothell

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1 Global Air Pollution: Science and Implications by Dan Jaffe, UW-Bothell Outline 1) The Clean Air Act and air quality standards 2) Cleaning up in the US 3) Growth in developing countries 4) Identification of global transport of pollutants 5) Why global transport matters My research team (R to L): Will Hafner, Duli Chand, Phil Swartzendruber, Mary Howisey, Dave Reidmiller, Jeremy Smith and Dr J (not shown Emily Fischer) Air Basic necessity for life (without O 2 we get brain damage in ~3 minutes); Lungs are readily irritated by noxious gases (e.g. O 3, SO 2, smoke, etc.); Lungs are also a good conduit for absorption into bloodstream of toxics such as Pb, CO, benzene, etc. Due to low mass of earth s atmosphere and sometimes poor dispersion, air can be readily polluted. History of major air pollution incidents Belgium, deaths; Donora, PA, deaths; London, deaths; New York, deaths. These incidents all occurred in heavily industrialized regions, under severe meteorological conditions (strong inversions with poor ventilation). One other important event in the 196s was when the Cuyahoga River (Cleveland) caught fire! Major Environmental Laws of the late 6 s and early 7 s National Environmental Policy Act (1969)- Required environmental review (EIS) before major governmental projects could be started; Creation of EPA (197); Clean Air Act (197)- Established national air quality standards and the initial regulatory framework of how those would be achieved; Clear Water Act Established national water quality standards. The Clean Air Act (CAA) One of the most complex laws ever written; Identifies 6 criteria pollutants (CO, O 3, SO 2, NOx, Pb, PM) Major revisions in 1977, 1985, 199, 1995 to deal with toxic chemicals, stratospheric ozone, etc; Considered by many to be a model environmental legislation and has been used as the basis for Clean Airs in many other countries. 1

2 NAAQS: National Ambient Air Quality Standards Level of pollutant that should not be exceeded in all areas of the country; Goal is to protect the health of all citizens, including sensitive populations; Based solely on health effects, economic considerations were not to be considered; NAAQS was then the basis for a comprehensive set of regulations on industry, vehicle manufacturers, states and cities and essentially established the industries of air pollution control technology and air quality monitoring. NAAQS should be re-evaluated by EPA every 5 years to ensure they are consistent with best scientific data. Criteria Pollutant SO 2 (g) NO 2 (g) CO (g) O 3 (g) Pb (s) Particulates (PM2.5/PM1) NMHCs (g) * Table of CAA Criteria Pollutants Most Important Sources Power plants, metal smelters, pulp mills All combustion, especially power plants and cars All combustion Secondary pollutant: Formed from reactions of NO 2 and NMHCs Leaded fuel Primary and secondary from all combustion Cars, industry Health and Ecological Effects Respiratory effects, contribute to acid rain Cause O3/smog formation contribute to acid rain Cardiovascular impacts Lung damage, asthma trigger, vegetation damage Brain and nervous system, particularly in children Asthma, bronchitis, premature death Major role in ozone formation * NMHCs are not formally considered criteria pollutants by the CAA, but are regulated in the CAA due to their contribution to ozone formation. CO and CO-Hemoglobbin Impact of CO on humans %CO-Hemoglobbin in the blood as a function of concentration and exposure time Emission Reductions due to the Clean Air Act CAA: Cost-Benefit Analysis In the 199 CAA amendments, congress required EPA to conduct a cost-benefit analysis on the CAA Final Report to Congress on Benefits and Costs of the Clean Air Act, Annual Costs: $25 billion (mainly compliance costs) Annual Benefits: $1.1 trillion (range trillion) Source: US EPA Mainly avoided deaths, avoided hospitalizations and avoided lost IQ points in children) A no brainer... 2

3 US NAAQS getting tougher PM2.5 Non-attainment areas O : 12 ppb -1 hr 1997: 85 ppb - 8 hr 28: 75 ppb - 8 hr PM 2.5 (24 hour) 1979: 9 * ug/m : 65 ug/m 3 28: 35 ug/m 3 * The early PM standard was for PM1. PM2.5 is estimated based on a PM2.5/PM1 ratio of.6 Orange: Areas that exceed only the annual std (15 ug/m 3 ). Yellow: Ares that exceed only the 24 hour std (35 ug/m 3 ). Red: Areas that exceed both. ~9 million people live in areas that don t meet the PM2.5 standard Non-attainment areas for 8-hour O 3 (85 ppb) Ozone in the Puget Sound Regions As of 21, ~13 million people in the US live in areas that don t meet the 85 ppb O 3 standard. (Designations based on 28 standards not yet completed) 1. Comes only from the Puget Sound Region 2. Comes only from the Puget Sound Region and California 3. Comes from local, regional, and sources as far away as China Most air pollution is from local sources, but as we move to lower standards, background air becomes more important. Background air Figure: EPA Atmospheric Deposition Handbook, 21. O3 ppb How important is O 3 in background air? Local pollution Global Pollution Natural Average concentration of background O 3 at Washington coast = 4 ppb Is the background increasing? Perhaps, there is some evidence. 3

4 The background is part natural and partly due to pollution from other countries. So what about the rest of the world? Europe, Japan and many other industrialized countries have adopted approaches that are rather similar to the CAA. Emissions of air pollutants are decreasing in most industrialized countries; China and many other countries are rapidly developing their economies, increasing their energy usage and emissions. Total energy consumption (1^15 BTU) 12 US 1 China Source: EIA CO2 emission (million metric tons CO2) China s energy use US China China and the US contribute 41% of all anthropogenic CO2. Source: EIA Source: WRI Cars in China (millions) 1% GDP 8% GDP 6% GDP New car sales in China But where will all this fuel come from??? Note that total vehicles (including, trucks, buses and motorcycles are about 3x these numbers. (US/China National Academies 23). Source: NYT 4

5 CO2 emissions: 198 CO2 emissions: 26 CO2 emissions: 26 Global total: 18.5 billion metric tons CO2 Source: EIA Global total: 29.2 billion metric tons CO2 Source: EIA Beijing Smog Observations from central Beijing by the BBC during the 28 summer Olympics According to the World Bank, 16 of 2 of the world s most polluted cities are in China. The measured PM1 concentration for August 2, 28 was 15 ug/m3 at mid-day. For reference, the WHO guideline is 5 ug/m3 averaged over 24 hours. Observations from central Beijing by the BBC during the 28 summer Olympics The measured PM1 concentration for August 4, 28 was 292 ug/m3 at mid-day. For reference, the WHO guideline is 5 ug/m3 averaged over 24 hours. Some interesting facts or are they factoids?? 1. 26: China surpasses US in total CO2 emissions. January 29: For the first time more cars were sold in China then in the US. By 21, about 3 different hybrids will be made and sold in China, some at half the price of US hybrids. Sources: 1) US Energy Information Agency 2) The web 3) The web 5

6 The Scientific Method Mean wind vectors for April 7 mb (~1, feet elevation) F i n d Funding Publications PHOBEA * Study Area The view from Cheeka Peak CPO Aircraft profiles * Photochemical Ozone Budget of the Eastern North Pacific Atmosphere. Mt. Bachelor, Oregon, 2.7 km above sea level Cheeka Peak 1 meter Sampling Tower Photo by Randy Hopfer Only high elevation/free tropospheric atmos. research site in western U.S. Continuous observations of CO, O 3, aerosols and Hg since 24. Frequent detection of Asian pollution plumes (Jaffe et al., 25; Weiss- Penzias et al., 26; 27; Swartzendruber et al., 26; Strode et al., 27) 6

7 Mt. Bachelor Observatory Vertical Profiles using Beechcraft Duchess Working in a blizzard After the storm Twin (piston) engine aircraft Unpressurized cabin Maximum flight altitude 6km, 4 hours useable flying time Maximum instrument payload ~24 kg Maximum instrument volume ~1.5m 3 Maximum power ~1 kw Available locally (Northway Aviation, 2min from lab) $25/hour including pilot. Heather, Dan and Isaac w/duchess Aircraft A chemical moment Understanding the chemical composition of the atmosphere plays a critical role in understanding the human impacts of pollution. Understanding the changes in the chemical composition are key to understanding global warming. Key chemical measurements CO: Infra-red spectroscopy CO 2 : Infra-red spectroscopy O 3 : UV spectroscopy Hg: UV fluorescence Hydrocarbons: Gas chromatography Nitrogen oxides: Chemiluminescence spectroscopy Acids (H 2 SO 4, HNO 3 ): Ion chromatography Peroxyacetyl nitrate: Gas chromatography Etc Global CO emissions from industrial sources 7

8 Its not just industrial sources Forest fires Industry Some example LRT events Transport of Asian mineral dust; Industrial pollution/o 3. Dust TOMS Aerosol Index (AI) for mid-april 21 April 8, 21 April 12, 21 April 14, 21 Satellites give useful information on large transport events, however this data is qualitative, lacks altitude and chemical information and is often obscured by clouds. To put this in perspective, we have identified about 15 transport events, but only 3 have been identifiable with satellite data. The April 21 dust event was a biggie Altitude (km) Aircraft vertical profile over Washington coastline April 14 th, 21 Flight 8, 14 April Spring Average +/-1sd.E+ 2.E-5 4.E-5 6.E-5 Aerosol Scatter 55nm (m -1 ) Altitude (km) CO (ppbv) Si Particulate data show that the dust mixed to the surface and moved across the US PM 1 How did the April 21 Asian dust episode influence air quality in several urban areas of the U.S.? Old std New std Jaffe et al., 23 8

9 Met tower and air sampling inlet Mt. Bachelor back trajectories, April 25, backward air trajectories for the times around the highest concentrations (1-16 GMT) and for a grid of locations surrounding the summit of MBO. Transport of Asian pollution to North America: April 25, 24 Observed ΔHg/ ΔCO ratios in Asian plumes Location Okinawa Mt.Bachelor ΔHg()/ΔCO (molar) x /- 1.7 (n=6) 6.2 +/- 1.8 (n=1) We have now detected many Asian pollution plumes at Mt. Bachelor (see Weiss-Penzias et al 27). Ratio in Asian plumes is ~5x higher than ratio seen in western US plumes and/or biomass burning plumes as seen at Mt.Bachelor. Hg/CO ratio appears to be good marker for Asian plume. BUT, this ratio is 2x larger then the expected Asian emissions ratio based on industrial Hg() inventories (Streets or Pacyna inventories). These results suggest a significant underestimate in the Asian mercury emissions inventory (see Jaffe et al., 25). Quotes from Yogi Berra Baseball is 9% mental. The other half is physical. Nobody goes there nowadays, it s too crowded. IPCC Emissions Scenarios for Asia in 25 (% Change from 199) Scenario A1B CO NO x 172 I didn t really say everything I said. A The future aint what it used to be! B B

10 Predicted surface O 3 in 25 (Using IPCC A2 scenario) Results from B. Lamb and J. Avise (WSU) Global cooperation These pollutants are related to energy use and development. The biggest issues are coal and increasing automobiles use in the developing world (energy reality). Currently the US and China are nearly equal in CO 2 emissions, but China is growing more rapidly. On a per capita basis, US emits about 6 times more CO 2 per person than does China (moral dimension). While many countries have signed on the Kyoto Protocol to limit CO 2, the US and China have not. The US has begun to play a leadership role on some issues, notably Hg and energy technology. Much more is needed. The developed world must show stronger leadership on global pollution issues. This is a very significant change in surface O 3. The largest contributor is due to the Boundary condition (BC) which is due to changes in emissions outside the U.S. Summary 1) We have identified numerous long-range transport coming from the Eurasian continent; 2) These episodes indicate multiple source types including industrial emissions, biofuels/biomass burning and mineral dust; 3) Occasionally, we see events that result in large enhancements at the surface and can contribute to air quality problems in the U.S.; 4) There are policy implications of this work especially for ozone, particulate matter and mercury. 5) Global cooperation on environmental matters is clearly essential for long-term sustainability of the planet. We even have a model the Montreal Protocols which have virtually eliminated chlorofluorocarbons and saved the ozone layer. Somebody s got to do it J.B. Dennison hanging from a rope to install an air sampler J.B. working on the gas inlet. DJ working on the tower Another day at the office? More information can be found on my group s website: 1