1. ACID RAIN

2. Acid Rain in Canada – Why all the fuss? Policies and Accords in North America Convention on Long-Range Trans boundary Air Pollution (1979) Eastern Canada Acid Rain Program (1985) First Sulphur Protocol (1985) Canada-US Air Quality Agreement (1991) Second Sulphur Protocol (1994) Protocol to Abate Acidification, Eutrophication and Ground-level Ozone (1999) Canada-wide Acid Rain Strategy for Post-2000 (1998)

3. Effects of Acid Rain the final result … - Increased acidity alters the chemistry of soil (allows leaching of toxins to occur) - Acid removes the waxy protective coating on leaves - This reduces plants’ ability to survive winter, drought and their ability to reproduce Forest Soils and Ecosystems

4. Effects of Acid Rain Human-made Structures and MaterialsHuman-made Structures and Materials - Limestone based buildings, sculptures, paint, as well as metal, glass, paper, leather, fabrics and rubber can be damaged or changed in some way - Structural damage to roadways, other building materials can occur 60 years agoToday Acropolis in Greece Today

5. Effects of Acid Rain Human HealthHuman Health - Can cause harmful effects to the cardiac and respiratory systems - Toxins leaching into environment (i.e. mercury) can be absorbed by the crops we harvest, the livestock we consume, and the fish we eat. In the year 2010, the public health benefits of the Acid Rain Program (implemented to reduce acidic emission levels) were estimated to be valued at $50 billion annually in the U.S.A., due to decreased mortality, hospital admissions, and emergency room visits.

6. Effects of Acid Rain on Aquatic Ecosystems Acid Rain lowers the pH of water in lakes, rivers, streams and wetlands Acid Rain lowers the pH of water in lakes, rivers, streams and wetlands Low pH can cause the leaching of toxic metals, such as mercury, iron & aluminum into the water Low pH can cause the leaching of toxic metals, such as mercury, iron & aluminum into the water Acidic pH can cause a disappearance of crustaceans, insects, mollusks & decomposing bacteria, a build-up of debris on lake bottoms, deformities in young fish, failure of fish and amphibian eggs to hatch, etc. Acidic pH can cause a disappearance of crustaceans, insects, mollusks & decomposing bacteria, a build-up of debris on lake bottoms, deformities in young fish, failure of fish and amphibian eggs to hatch, etc. Animals higher on food chain lose food sources, bio- accumulation/bio-amplification of toxins occurs Animals higher on food chain lose food sources, bio- accumulation/bio-amplification of toxins occurs Limestone helps to “buffer” the effects of acid rain, but areas with granite bedrock (i.e. Canadian Shield) have little buffering ability! Calcium that was present in these ecosystems is severely depleted! Limestone helps to “buffer” the effects of acid rain, but areas with granite bedrock (i.e. Canadian Shield) have little buffering ability! Calcium that was present in these ecosystems is severely depleted! Good indicator species for acid rain problem Bioaccumulation, or the uptake of toxin (i.e. PCBs) occurring at one trophic level, is taking place at each level of the food chain. (i.e. fish eats many worms and toxin builds up in that fish’s fatty tissues) Biomagnification, or the increase of toxin in the fatty tissues of each successive organism, occurs all the way up the food chain! The top predator (eagle) contains the most toxin while each of the lowest (plankton) contain a small amount of toxin.

7. What is Acid Rain? Rain has a natural pH of 5.6 This is due to CO 2 mixing with water to form carbonic acid in the atmosphere, lowering rainwater’s pH from 7 to 5.6. Acid precipitation is any precipitation with a pH less than 5.6. ACIDICALKALINE or BASIC

8. Our Bad Guys … So What Causes Acid Rain? So What Causes Acid Rain? SO 2 NO x

9. Natural Sources of SO 2 in the Atmosphere Volcanic Emissions Sea Spray Forest Fires SO 2

10. Non- Natural Sources of SO 2 in the Atmosphere Coal-burning plants & non-ferrous smelting Burning of fossil fuels 85-90% of sulphur entering the atmosphere is 85-90% of sulphur entering the atmosphere is from non-natural sources

11. Sources of Acid Rain (SO 2 ) Sources of Sulphur Dioxide Emissions from www.ec.gc.ca/acidrain/acidfact.html

12. Chemical Reactions Many metals (i.e.: nickel) occur in nature as sulphide ores. To convert them to free metals, the ores are smelted using heat, and sulfur is released as SO 2. 2 NiS + 3 O 2 2 NiO + SO 2 In the air, SO 2 mixes with water vapour and undergoes chemical changes to form sulphuric acid, or “acid rain”. Heat SO 2 + H 2 0 oxidation H 2 SO 4 (sulphuric acid)

13. Non- ferrous Smelting of Ores, Coal Burning = Sulphur Dioxide = Acid Precipitation

14. So how do we stop this SO 2 ? A cleaning or “scrubber” process using calcium carbonate (limestone) is often used to remove about 90% of SO 2 before emission. The remaining product, calcium sulphate, must be buried in a landfill, and carbon dioxide is released as a by-product. WHY WOULD CO 2 RELEASE BE BAD? CaCO 3 + SO 2 CaSO 3 + CO 2 Before scrubber After scrubber

15. The SO 2 Situation Courtesy of Environment Canada

16. Natural Sources of NO x in the Atmosphere Volcanic Emissions Decomposition of Organic Materials NO x

17. Non-Natural Sources of Non-Natural Sources of NO x in the Atmosphere Burning of other fossil fuels Exhaust from vehicles 60-70% of nitrogen oxides in the atmosphere come from non-natural sources, particularly vehicle exhaust 60-70% of nitrogen oxides in the atmosphere come from non-natural sources, particularly vehicle exhaust

18. Sources of Acid Rain (NO x ) Sources of Nitrogen Oxide Emissions from www.ec.gc.ca/acidrain/acidfact.html

19. Chemical Reactions Nitrogen to Nitric AcidNitrogen to Nitric Acid NO x in the atmosphere mixes with water vapour to form nitric acid. The speed of these oxidation reactions can increase if sunlight is present. NO x + H 2 0 HNO 3 (nitric acid) Oxidation Oxidation Nitrogen given off by automobiles is released to the air in the form of NO x

20. The NO x Situation Courtesy of Environment Canada

21. Acid Rain in Canada Problem Areas: yellow blue – critical load not a concern for 2010 and beyond red to yellow – critical load will exceed levels needed for environment to recover and reduce current acidity (in other words acidity will contine to increase after 2010 ) Map of areas sensitive to acid rain – Ministry of the Environment

22. Critical Load and Why It’s Important Critical load values kg/ha/year of sulphate in precipitation The critical load is the highest level of acid rain that an ecosystem can receive over the long term that won’t result in harmful effects to the environment (the load the environment can tolerate and keep pH levels above 6). The colours in the map represent the maximum load the area can tolerate (see scale at upper left). The numbers in the map show the amount of sulphate presently precipitating on these areas. Courtesy Environment Canada

23. So why are some areas affected more than others by acid rain? Soils and bedrock determine an ecosystems ability to tolerate high levels of acid precipitation. Remember the Scrubbers? Industry uses calcium carbonate (limestone) to remove sulphates from their emissions. People learned to do this from nature! Soils containing limestone have a greater “buffering capacity” or ability to absorb the H + cations that cause acidity. Soils/bedrock with little limestone (like the granite on the Canadian Shield) cannot absorb any H + cations, so the environment becomes acidic quickly.

24. This lake has a limestone substrate (bottom) that acts as a buffer to acid precipitation. Note the healthy emergent vegetation along the shoreline and little algae is present. This Canadian Shield lake has been damaged by acid precipitation. Note its banks have little if any vegetation. Algae coats the bottom and no lifeforms are present. This lake is located in the Temagami area of Northern Ontario, where granite bedrock and soils allow no buffering of acid precipitation. Question: Acid Rain Sensitive Lake Environment or Not? Both lakes may be sensitive to acidification depending on the amount of acid precipitation they receive, but the granite soil based lake is less able to cope with acid precipitation

25. Here’s the problem! Winds

26. Acid Precipitation is being dumped onto our Canadian Sensitive Areas! Note typical Canadian Expression of Shock and Horror

27. Changes in pH of Precipitation 1983-2001 With the reductions in emissions, pH seems to be improving … but not as well as we’d expect!

28. It looks like things are improving with SO 2 !

29. So Why Haven’t pH levels Improved? Nitrate levels are still a problem and may increase in future!

30. How can we reduce nitrogen emissions? Cleaner-burning enginesCleaner-burning engines “Hybrid” vehicles“Hybrid” vehicles Cleaner fuels – i.e. gasoline that emits 90% less SO 2 and NO xCleaner fuels – i.e. gasoline that emits 90% less SO 2 and NO x Alternative fuels – ethanol, methanol etc.Alternative fuels – ethanol, methanol etc. NO x emission controls for vehicles and industryNO x emission controls for vehicles and industry More eco-friendly transportation alternativesMore eco-friendly transportation alternatives the Harley of the new Millennium?

31. Are ecosystems able to recover from Acid Rain? Yes!Yes! Southern Ontario has seen improved water quality and pH levels, but waters in the Canadian Shield have shown little improvement Challenges We FaceChallenges We Face Sensitive Areas - Drought and dry weather cause release of sulphates accumulated in soil. These sulphates are washed into aquatic environments when precipitation does occur, further depleting calcium levels in ecosystems already low in calcium. 75% The U.S.A. will meet their S0 2 and NO x emission target levels set out in the 1991 agreement, but scientists estimate a further reduction of 75% is necessary to protect our Sensitive Canadian Shield waters which are prone to acidification

32. Factors that Affect pH of Water and Soils Today Calcium that was present in Sensitive Areas is now used up! Many fundamental organisms in the food chain (like Daphnia which is a Keystone Species) require calcium to develop! Therefore, even though lake acidity levels are slowly improving, ecosystems are not. It will take much time, study, effort and continued emission controls to allow nature to recover. Calcium that was present in Sensitive Areas is now used up! Many fundamental organisms in the food chain (like Daphnia which is a Keystone Species) require calcium to develop! Therefore, even though lake acidity levels are slowly improving, ecosystems are not. It will take much time, study, effort and continued emission controls to allow nature to recover. Ecosystems are based on keystone life-forms like this Daphnia, which require calcium to exist. Its simple … no calcium, no ecosystem!

33. The End Result … hopefully healthy aquatic and terrestrial ecosystems like this … healthy aquatic and terrestrial ecosystems like this …

34. not this! It’s up to us! It’s up to us!

35. Help Conserve Our Natural Resources! © Lower Thames Valley Conservation Authority 2016 No part of this presentation is to be copied or shared without permission.

36. Monitoring Acid Rain Canadian Air and Precipitation Monitoring Network (CAPMoN)

37. Wet Only Deposition Collector Monitoring Acid Rain Here at Longwoods Standard Rain Gauge Nipher Shielded Snow Gauge Precipitation Collection

38. Monitoring Acid Rain Air Filter Measurement Sampling Head Assembled 3 Stage Filtering Pack 3 Stage Filtering Pack and filtration sections Air Filters Air is sucked in from outside. Different particle filters in each filter pack collect “dry deposition” particles and gases. -a Teflon filter collects sulphate, nitrate, chloride, potassium, ammonia, magnesium and sodium. -a Nylon filter collects nitrogen oxide gas. -a Cellulose filter collects sulphur dioxide gas. TeflonNylon Cellulose Dry Deposition Collection Sequential Air Sampler

39. Help Conserve Our Natural Resources! © Lower Thames Valley Conservation Authority 2016 No part of this presentation is to be copied or shared without permission.