Long descriptions of the figures and tables contained in report

Figure 1, Total Canadian Emissions of SO2 from acid rain sources, 1980 - 2010

Figure1 shows Canadian national SO2 emissions in millions of metric tons from acid rain sources from 1980 to 2010. The figure shows a decreasing trend. In 2010, Canada’s total SO2 emissions were 1.4 million metric tons, or about 57 percent below the national cap of 3.2 million tonnes. This also represents a 57 percent reduction from Canada’s total SO2 emissions in 1990.

Figure 2, SO2 Emissions from the Clear Air Interstate Rule SO2 Annual Program and Acid Rain Program Sources, 1990-2011

Figure 2 depicts combined emission and compliance data for both the Acid Rain Program (ARP) and Clean Air Interstate Rule (CAIR). In 2011, there were 3,345 affected electric generating units at 951 facilities in the CAIR SO2 and NOx annual programs. Annual SO2 emissions from sources in the CAIR SO2 program fell from 9 million short tons (8.2 million metric tons) in 2005 when CAIR was promulgated to 3.9 million short tons (3.5 million metric tons) in 2011, a 57 percent reduction. Between 2010 and 2011, SO2 emissions fell 543,000 short tons (493,600 metric tons), or 12 percent.

Figure 3, U.S. Title IV Utility Unit NOx Emissions from all Acid Rain Program (ARP) Sources, 1990 - 2011

Figure 3 depicts U.S. NOx emissions in millions of short tons from coal-fired electric utility units affected by the NOx component of Title IV of the 1990 Clean Air Act. These include NOx program-affected sources and Title IV sources affected by the NOx program. With a few exceptions the trends are decreasing over time. In 2011, 930 coal-fired units at 375 facilities were subject to the ARP NOx program. Emissions of NOx from all sources covered by the ARP were 1.9 million short tons (1.7 million metric tons) in 2011.

Table 1, Units and SO2 Emissions Covered by Monitoring Method for the Acid Rain Program (ARP), 2011

Table 1 shows the amount of SO2 emissions monitoring using continuous emission monitoring systems (CEMS) for primary fuels such as coal, gas, oil and other (which includes primarily wood, waste or other non-fossil fuel) in 2011. Affected sources are required to meet stringent quality assurance and control requirements and report hourly emission data in quarterly electronic reports to U.S. EPA.

Figure 4, 1990 Annual Wet Sulfate Deposition

Figure 4 shows the U.S.-Canada spatial pattern of wet sulfate (sea salt corrected) deposition in kilograms/hectare/year for 1990. It also shows that wet sulfate deposition is highest in eastern North America around the lower Great Lakes, with a gradient following a southwest-to-northeast axis running from the confluence of the Mississippi and Ohio Rivers through the lower Great Lakes. The patterns for 1990, 2000 and 2010 illustrate that significant reductions occurred in wet sulphate deposition in both the eastern U.S. and eastern Canada.

Figure 5, 2000 Annual Wet Sulfate Deposition

Figure 5 shows the U.S.-Canada spatial pattern of wet sulfate (sea salt corrected) deposition in kilograms/hectare/year for 2000. It also shows that wet sulfate deposition is highest in eastern North America around the lower Great Lakes, with a gradient following a southwest-to-northeast axis running from the confluence of the Mississippi and Ohio Rivers through the lower Great Lakes.

Figure 6, 2010 Annual Wet Sulfate Deposition

Figure 6 shows the U.S.-Canada spatial pattern of wet sulfate (sea salt corrected) deposition in kilograms/hectare/year for 2010. It also shows that wet sulfate deposition is highest in eastern North America around the lower Great Lakes, with a gradient following a southwest-to-northeast axis running from the confluence of the Mississippi and Ohio Rivers through the lower Great Lakes. The patterns for 1990, 2000 and 2010 illustrate that significant reductions occurred in wet sulphate deposition in both the eastern U.S. and eastern Canada.

Figure 7, 1990 Annual Wet Nitrate Deposition

Figure 7 shows the U.S.-Canada spatial pattern of wet nitrate deposition in kilograms/hectare/year in 1990. The pattern for wet nitrate deposition shows a similar southwest to-to-northeast axis, but the area of highest nitrate deposition area is north of the region with the highest sulphate deposition. Reductions in wet nitrate deposition have generally been more modest than for wet sulphate deposition.

Figure 8, 2000 Annual Wet Nitrate Deposition

Figure 8 shows the U.S.-Canada spatial pattern of wet nitrate deposition in kilograms/hectare/year in 2000. The pattern for wet nitrate deposition shows a similar southwest to-to-northeast axis, but the area of highest nitrate deposition area is north of the region with the highest sulphate depositions. Reductions in wet nitrate deposition have generally been more modest than for wet sulphate deposition, except during 2000 to 2010, when large NOx emission reductions occurred in the U.S., and to a lesser degree in Canada.

Figure 9, 2010 Annual Wet Nitrate Deposition

Figure 9 shows the U.S.- Canada spatial pattern of wet nitrate deposition in kilograms/hectare/year in 2010. The pattern for wet nitrate deposition shows a similar southwest to-to-northeast axis, but the area of highest nitrate deposition area is north of the region with the highest sulphate depositions. Reductions in wet nitrate deposition have generally been more modest than for wet sulphate deposition, except during 2000 to 2010, when large NOx emission reductions occurred in the US, and to a lesser degree in Canada.

Figure 10, Annual Average Standard Visual Range in the Contiguous United States, 2006-2010

Figure 10 shows the annual average standard visual range within the U.S. for the period 2006-2010.in kilometres in the contiguous U.S. “Standard visual range” is defined is defined as the farthest distance a large dark object can be seen during daylight hours. The visual range under naturally occurring conditions without human-caused pollution in the U.S. is typically 45 to 90 miles (75 to 140 km) in the east and 120 to 180 miles (300 to 300 km) in the west.

Figure 11, PEMA Region and Clean Air Interstate Rule (CAIR)

Figure 11 depicts a map of the eastern states in the U.S. illustrating 22 CAIR states and the District of Colombia that are controlled for both fine particles and ozone, 14 of which are located within the Pollution Emission Management Area (PEMA), and CAIR states that are not in the PEMA. U.S. EPA stopped administering the NOx Budget Trading Program under the NOx SIP call following the 2008 ozone season. Starting in 2009, the NOX annual and ozone season program under CAIR took effect,

Table 2, Affected Units in CAIR NOx and SO2 Annual and CAIR NOx Ozone Season Programs

Table 2 shows that in 2011, there were 3,307 electricity generating units (EGUs) and industrial facility units at 954 facilities in the CAIR NOx ozone season program, of these, 1,906 were covered units in the Ozone Annex PEMA. The CAIR NOx ozone season program includes EGUs, as well as in some states large industrial units that produce electricity or steam primarily for internal use and that have been carried over from the NOx Budget Trading Program.(NBP).

Figure 12, Ozone Season Emissions from CAIR NOx Ozone Season Sources

Figure 12 depicts ozone season emissions in thousand short tons under the legacy NOx Budget Trading Program and new CAIR units from 2008 to 2011. The ozone season NOx emissions show a decreasing trend. From 2010 to 2011, ozone season NOx emissions from sources in the CAIR NOx ozone season program decreased by 28,000 short tons (24.455 metric tons) (5 percent), reversing a on-year increase in emissions from 2009 to 2010. Units in the seasonal ozone program reduced their overall NOx emissions from 1.5 million short tons (1.4 million metric tons) in 2000 to 566,000 short tons (514,545 metric tons) in 2011.

Figure 13, Canadian Transportation NOx and VOC PEMA Emissions and Projections, 1990-2025

Figure 13 depicts Canadian NOx and VOC PEMA emissions and projections from transportation sources in thousand metric tons from 1990 to 2025. NOx and VOC emissions from both on-road and off-road vehicles in the PEMA are presented. The figure illustrates that NOx and VOC emissions from transportation sources in the PEMA are expected to decrease by 60 percent and by nearly 62 percent, respectively by 2025 from 1990 levels.

Figure 14, Canadian NOx and VOC PEMA Emissions and Projections

Figure 14 depicts Canadian NOx and VOC emissions and projections in metric tons and short tons for 1990, 2010 and 2025. The specific NOx and VOC emission reduction obligations in the Ozone Annex reduced annual NOx emissions in the PEMA by 43 percent and annual VIOC emissions in the PEMA by 42 percent by 2010, from 1990 levels. Annual NOx and VOC emissions in the PEMA are expected to decrease from 1990 levels by 53 percent and 52 percent, respectively, by 2025.

Figure 15, U.S. NOx and VOC PEMA Emissions and Projections

Figure 15 depicts U.S. NOx and VOC emissions and projections in million short tons and metric tons for 1990 and 2012. The specific emission reduction obligations in the Ozone Annex are estimated to reduce annual NOx emissions in the PEMA by 63 percent from 1990 levels and to reduce annual VOC emissions in the PEMA by 61 percent from 1990 levels by 2012.

Table 3, PEMA Emissions, 2010

Table 3 shows preliminary 2010 U.S. and Canadian emissions of NOx and VOCs by emissions category in the PEMA in short tons and metric tons, respectively. Annual and ozone season emissions are presented.

Figure 16, U.S. NOx Emission Trends in PEMA States, 1990-2010

Figure 16 depicts U.S. NOx emission trends (in thousand short tons and metric tons) in the PEMA states from 1990 to 2010. This includes trends for on-road transportation, electric power generation, nonroad transportation, industrial sources, non-industrial fuel sources and other anthropogenic sources. For NOx most of the emission reductions come from on-road mobile sources and electric power generation.

Figure 17, U.S. VOC Emission Trends in PEMA States, 1990-2010

Figure 17 depicts U.S. VOC emission trends (in thousand short tons and metric tons) in the PEMA states from 1990 to 2010. This includes trends for solvent utilization, on-road transportation, nonroad transportation, industrial sources, non-industrial fuel sources and other anthropogenic sources. The reduction in VOC emissions are primarily from on-road and nonroad mobile sources and solvent utilization.

Figure 18, Canada NOx Emission Trends in the PEMA Region, 1990-2010

Figure 18 depicts Canada’s NOx emission trends (in thousand metric tons and short tons) in the PEMA region from 1990 to 2010. This includes trends for on-road transportation, nonroad transportation, industrial sources, electric power generation, non-industrial fuel sources and other anthropogenic sources. For NOx, most of the emission reductions come from on-road mobile sources and electric power generation, with increases in non-industrial fuel combustion and other anthropogenic sources.

Figure 19, Canada VOC Emission Trends in the PEMA Region, 1990 -2010

Figure 19 depicts Canada’s VOC emission trends (in thousand metric tons and short tons) in the PEMA region from 1990 to 2010. This includes trends for solvent utilization, on-road transportation, nonroad transportation, industrial sources, non-industrial fuel sources and other anthropogenic sources. VOC emissions reductions are primarily from on-road mobile source, electric power generation, industrial sources and solvent utilization, with a skight increase in non-industrial fuel combustion.

Figure 20, Ozone Concentrations along the U.S.-Canada Border (Three-Year Average of the Fourth Highest daily Maximum 8-Hour Average), 2008-2010

Figure 20 depicts a map of ozone concentrations along the U.S.-Canada border (three-year average of the fourth highest daily maximum 8-hour average) in ppb from 2008 to 2010. Higher ozone levels occur in the lower Great Lakes-Ohio Valley region and along the U.S. East Coast. Lowest values are generally found in the West and Atlantic Canada. Levels are generally higher downwind of urban areas, as can be seen in the western portions of lower Michigan, though the full detail of urban variation is not shown.

Figure 21, Annual Average Fourth Highest Maximum 8-Hour Ozone Concentration for Sites within 500 km of the U.S.-Canada Border, 1995-2010

Figure 21 depicts U.S. and Canada annual fourth highest maximum 8-hour ozone concentration for sites within 500 km of the U.S.-Canada border in ppb from 1995 to 2010. Ozone levels have decreased over this time period. The apparent decreasing trend in ozone levels from 2002 is in part due to the cool, rainy summer of 2004 and 2009 in eastern North America.

Figure 22, Average Ozone Season (May-September) 1-Hour NOx Concentration for Sites within 500 km of the U.S.-Canada Border, 1995-2010

Figure 22 depicts Canada and U.S. ozone season 1-hour NOx concentration for sites within 500 km of the Canada-U.S. border in ppb from 1995 to 2010. The NOx data shown in Figure 22 represent measurements for the “ozone season” (i.e., May through September) and indicate a decline in the ambient level of NOx.

Figure 23, Average Ozone Season (May-September) 24-Hour VOC Concentrations for Sites within 500 km of the U.S.-Canada Border, 1997-2010

Figure 23 depicts Canada and U.S. annual average 24-hour VOC concentration for sites with 500 km of the Canada-U.S. border in ppb from 1997 to 2010. The VOC data shown in Figure 23 represent measurements for the “ozone season” (i.e., May through September) and indicate a decline in the ambient level of VOCs.

Figure 24, Network of Monitoring sites Used to Create Graphs of Ambient Ozone, NOx, and VOC Levels

Figure 24 depicts a map of the network of monitoring sites in eastern Canada and the eastern U.S. that were used to create the ambient levels of ozone, NOx and VOC graphs presented in Figures 21, 22 and 23.

Figure 25, U.S. and Canadian National Emissions by Sector for Selected Pollutants, 2010

Figure 25 depicts U.S. and Canada national emissions by sector for selected pollutants in 2010. It includes six pie charts. This figure shows that SO2 emissions in the United States stem primarily from coal-fired combustion in the electric power sector and industrial boilers. Canadian SO2 emissions come mostly from the nonferrous smelting and refining industry, upstream petroleum industry, and electric power generation utilities. The relative contribution from electric power generation utilities is lower in Canada due to the large hydroelectric and nuclear capacity in place, and differences in population and demand. The distribution of NOx emissions in the two countries is similar, with nonroad and on-road vehicles accounting for the greatest portion of NOx emissions.

Figure 26, National SO2 Emissions in the United States and Canada from All Sources, 1990-2010

Figure 26 depicts SO2 emission trends in the U.S. and Canada in million short tons and metric tons, respectively, from 1990 to 2010. In the U.S., the major reductions in SO2 emissions came from electric power generation sources as well as industrial and commercial fuel combustion sources. In Canada, the reductions in SO2 came from the nonferrous smelting and refining industry, and electric power generation utilities.

Figure 27, National NOx Emissions in the United States and Canada from All Sources, 1990-2010

Figure 27 depicts NOx emission trends in the U.S. and Canada in million tons and million tonnes, respectively, from 1990 to 2010. In the U.S., the major reductions in NOx emissions came from on-road and nonroad mobile sources, electric power generation sources, and other industrial fuel combustion sources. In Canada, the NOx reductions were from on-road mobile sources. electric power generation utilities and the mining and rock quarrying industry.

Figure 28, National VOC Emissions in the United States and Canada from All Sources, 1990-2010

Figure 28 depicts VOC emission trends in the U.S. and Canada in million short tons and metric tons, respectively, from 1990 to 2010. In the U.S., the reductions in VOC emissions came from on-road and nonroad mobile sources, solvent utilization, and petroleum storage and transport. In Canada, the VOC reductions came from on-road mobile sources and the downstream petroleum industry, with additional reductions from various industrial sectors such as chemical, pulp and paper, wood products, and iron and steel industries.

Figure 29, AIRNow Map Illustrating the Air Quality Index (AQI) for 8-Hour Ozone

Figure 29 depicts an example of the kind of maps available on AIRNow website which display pollutant concentration data expressed in terms map of the colour-coded Air Quality index (AQI). The figure shows the AQI for 8-hour ozone in the U.S.

Figure 30, Ozone and Continuous PM2.5 Monitors Reporting to the NAPS Canada-wide Air Quality Database, 2010

Figure 30 depicts the number of PM2.5 and ozone sites reporting to the Canada-wide air quality database in 2010. These sites are located in over 100 communities, including all communities with a population greater than 100,000.. In total, these communities account for 75 percent of the Canadian population.

Table 4, U.S. Air Quality Monitoring Networks

Table 4 provides a summary list of major routine operating air monitoring networks in the U.S. The majority of air quality monitoring performed in the U.S. is carried out by state, local and tribal agencies in four major networks of monitoring stations: State and Local Air Monitoring Stations (SLAMS). Photochemical Assessment and Monitoring Stations (PAMS), PM2.5 Chemical Speciation Network (CSN) and air toxics monitoring stations.

Figure 31, Eastern North American Sites Reporting Data to the ICP Waters Database (in green) and the 13 Additional Stations in Ontario (in yellow)

Figure 31 shows the 96 Northern American ICP sites that were grouped into six regions (Maine and Atlantic Canada, Vermont and Quebec, Adirondacks, Appalachian Plateau, Virginia Blue Ridge and Ontario) and analyzed for acidification and or recovery trends.

Figure 32, Long-Term Monitoring Program Sites

Figure 32 depicts the long-term monitoring program sites that are designed to track changes in surface water chemistry in the four acid sensitive regions: New England, the Adirondack Mountains, the North Appalachian Plateau, and the central Appalachians.

Table 5, Regional Trends in Sulfate, Nitrate, ANC, and DOC at LTM Sites, 1990-2009.

Table 5 shows that significant improving (decreasing) trends in sullfate concentrations from 1990 to 2009 are found at nearly all monitoring sites in New England, the Adirondacks, and the Catskill Mountains/Northern Appalachian Plateau. In the Central Appalachians only 12 percent of monitored streams showed a decreasing sulfate trend, while 14 percent of monitored streams actually increased, despite decreasing sulfate deposition.

Figure 33, Critical Load Exceedance Probability, 2002 and 2006

Figure 33 shows four maps of Canada depicting the probability of exceeding a critical load that was evaluated for the 2002 and 2006 total for sulphur and nitrogen deposition respectively. The analysis points to high probabilities of critical loads exceedance in many parts of the country, even in the later year of study (2006), which support the need for further emission reductions.

Figure 34, Lake and Stream Exceedances of Estimated Critical Loads for Total Nitrogen and Sulfur Deposition, 1989-1991 vs. 2008-2010.

Figure 34 depicts a map of north-eastern U.S. for which the critical loads were measured to deposition for the period before the implementation of the Acid Rain Programs (ARP) (1989-1991 and for a recent period after ARP and CAIR implementation (2008-2010). Overall, the analysis shows that emission reductions achieved by the ARP and CAIR so far have resulted in improved environmental conditions and increased ecosystem protection in the eastern United States.

Figure 35, Existing Monitoring During the 2010-11 Baseline Year and Proposed Monitoring by 2015.

Figure 35 depicts a map of Alberta which shows the existing monitoring in 2011 and the monitoring proposed by year 2015 of the oil sands region under a Joint Implementation Plan between the Governments of Canada and Alberta.

Figure 36, Changes in Annual Wet Sulfate and Wet Nitrate Deposition, 1990-2010

Figure 36 presents maps of annual wet sulphate and wet nitrate deposition for the years 1990 and 2010. The maps show the vast change in wet sulphate and nitrate deposition since the Air Quality Agreement started in 1991.

Figure 37, Ozone Annex PEMA

Figure 37 shows the transboundary ozone region or PEMA that include parts of southern Quebec and southern and central Ontario in Canada and, in the U.S., 18 midwestern and eastern states, and the District of Columbia

Figure 38, Ozone Concentrations along the U.S.-Canada border, 2000-2008

Figure 38 shows four maps from the four Progress Reports since 2004 that illustrate how ozone concentration levels are changing across the U.S.-Canada border area, with ozone levels decreasing significantly in the central eastern area and increasing slightly in the western area. The maps show ozone concentrations along the U.S.-Canada border (three-year average of the fourth highest daily maximum 8-hour average) in ppb for the time periods, 2000-2002, 2002-2004, 2004-2006, and 2006-2008.

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