North American emissions

Legislation enacted by both Canada and the United States (see the US-Canada Air Quality Accord, 1991) will, when implemented, reduce the North American emissions of sulphur dioxide by about 50% based upon the 1980 baseline. These projected emission fields have been appplied in the atmospheric source-receptor models that were described above, to provide a projected deposition field for acidic sulphate that would be expected (14). The predicted sulphate deposition fields have then subsequently been appUed in aquatic effects models that provide estimates of regional surface water acidification distributions (50). The regional acidification profiles have then been used in a model of fish species richness (51) that results in an estimate of the expected presence of fish species as compared to that expected in an unacidified case. 

Impact of North American Emissions on Wet Deposition to the Western Atlantic Ocean. Wet deposition has been collected by event during WATOX at two sites on Bermuda, one site near Lewes, Delaware, and on board ships. These wet-deposition samples have been analyzed for acidic species, metals, and organic compounds. This section discusses our interpretation of the marine precipitation-chemistry data and the results of our analyses as well as the influence of North American emissions on precipitation composition. 

The Impact of North American Emissions on the Composition of the Atmosphere over the Western Atlantic Ocean. As part of WATOX-82 (August 1982) and WATOX-83 (January and February 1983), General Motors Research Laboratories operated air-monitoring sites on the Atlantic coast near Lewes, Delaware, and on the southwest coast of Bermuda, 1250 km to the southeast of the Delaware site. Their overall purpose was to study the transformations of the principal acid-precipitation precursors, NOx and SOx species, as they were transported under conditions not complicated by emissions from local sources. Three papers have resulted from this study (16. 17. 18). 

The Influence of North American Emissions on the Surface Ocean. The increased deposition of fixed nitrogen to an ocean has the potential to affect the primary productivity in the surface of that ocean. 

North American emission requirements Two sets of US Federal emission standards are defined for cars and light-duty trucks, Tier 1 and Tier 2. Tier 1 requirements were published in 1991 and fully implemented in 1997. Tier 2 standards were adopted in 1999 and began to be phased in commencing in 2004. The emission targets for each vehicle depend upon its weight and service type. 

To assess the prospects for links between North American emissions trading schemes, the next section sets the context by reviewing greenhouse gas emissions and climate change initiatives at the national and state/provincial level in the USA and Canada. The existing and proposed emissions trading schemes are described in Section 3. Overlaps between the national and the state/provincial schemes are discussed in Section 4. Section 5 discusses potential links by US and Canadian schemes with each other and with other schemes. Conclusions are drawn in Section 6. 

Canada plans to move from emission-intensity targets to fixed emission caps between 2020 and 2025, but might do so earlier to facilitate development of a North American emissions trading scheme. Since one, perhaps the main, reason for changing the design would be to link with a US (and possibly Mexican) scheme, it is safe to assume that the modified Canadian scheme would include additional linking provisions. 

S. Albu, "California s Regulatory Perspective on Alternate Euels," 13th North American Motor Vehicle Emissions Control Conf (Tampa, Fla., Dec. 11—14, 1990), Mobile Source Division, California Air Resources Board, El Monte, Calif. 

Environmental. Stringent environmental laws require that nitrogen oxides (NO ) and sulfur oxides emission from furnaces be drastically reduced. In many parts of the world, regulations require that NO be reduced to 70 vol ppm or lower on a wet basis. Conventional burners usually produce 100 to 120 vol ppm of NO. Many vendors (McGill, John Zink, and North American) are supplying low NO burners. 

While natural emissions of sulphur and nitrogen exist, over 95% of the sulphur emissions in eastern North America are of man-made origin. Natural sources of nitrogen are less well estabUshed but are estimated to be small when compared to the man-made emissions 21). The distribution of North American sources of sulphur dioxide and nitrogen oxides are shown in Figure 2. In 1980, which has served as the base period for the assessment of emissions,it was estimated that sulphur dioxide emissions were Canada - 4.8 million tonnes (metric) and the United States - 24 million tonnes nitrogen oxides emissions were Canada - 1.8 million tonnes and the United States - 20 million tonnes. The more recent trends for sulphur dioxide emissions in Canada and the emission control limits are shown in Figure 3 14). 

Moran, M. D. (1997). Evaluation of the impact of North American SO2 emission control legislation on the attainment of SO critical loads in eastern Canada. Paper 97-TA 28.05, 90th AWMA Annual Meeting, Air Waste Management Association, Pittsburgh. 

Hardwood species such as oaks, poplars, aspen, and ironwood are generally isoprene emitters. However, even within plant families, not all species are isoprene emitters. For example, while North American oaks emit isoprene, many European oak species do not. For example, Steinbrecher et al. (1997) measured the emissions of isoprene and monoterpenes from five species of Mediterranean oak two of them were strong isoprene emitters, whereas the other three did not emit significant amounts. Similarly, Kesselmeier et al. (1998) measured emissions of isoprene and monoterpenes from a Holm oak and a white oak growing side by side the white oak was a strong isoprene emitter, whereas the Holm oak was a strong monoterpene emitter. 

Kesselmeier, J., K. Bode, L. Schafer, G. Schebeske, A. Wolf, E. Brancaleoni, A. Cecinato, P. Ciccioli, M. Frattoni, L. Dutaur, J. L. Fugit, V. Simon, and L. Torres, Simultaneous Field Measurements of Terpene and Isoprene Emissions from Two Dominant Mediterranean Oak Species in Relation to a North American Species, Atmos. Ent iron., 32, 1947-1953 (1998). 

Laursen, K. K P. V. Hobbs, L. F. Radke, and R. A. Rasmussen, Some Trace Gas Emissions from North American Biomass Fires... 

Commission for environmental cooperation of North America, North American Power Plant Air Emissions, Canada (2004)... 

The major anthropogenic sources of PCDD/F emissions to the North American atmosphere that contribute to TEQ deposition in the Great Lakes have been estimated [28,29]. The fraction of total estimated atmospheric TEQ deposition to Lake Superior in 1996 from various sources is shown in Fig. 2. 

Scholtz MT, McMillan AC, Slama C, Li YF, Ting N, Davidson K (1997) Pesticides emission modelling. Development of a North American pesticide inventory. Report CGEIC-1997-1, 1-242, Canadian Global Emissions Interpretation Centre, Toronto, ON, Canada... 

MV EG MVMA different viscosities at 100°C. Fluids with very high natural viscosity indexes, such as some synthetic fluids, are also classified as multiviscosity. Motor Vehicle Emission Group (Europe). Motor Vehicle Manufacturers Association (U.S. passengers cars). A North American OEM association. As part of ILSAC, it participates in promoting the ILSAC engine oil standards. 

Miller, J. M. Tellus. in press) have examined the transport of North American sulfur emissions across the north Atlantic Ocean to Europe. In a review of available precipitation-sulfate data from the north Atlantic and adjacent coastal regions, they report a concentration field consistent with known source distributions and meteorological factors. The excess sulfate concentration of marine background... 

At the distance of the European west coast, North American anthropogenic emissions account for approximately 4 jieq/1 in precipitation. This is less than the marine background of 6-8 peq/1 and much less than the annual average excess [SO ] value of approximately 30 jieq S/l appropriate for much of the coastal region. Whelpdale et al. conclude, therefore, that, on the average, the amount of North American anthropogenic sulfur reaching Europe is small compared to that from other sources. 

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