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Canada’s Energy Resources a) Coal – most abundant fossil fuel in the world Canada holds 6.6 billion tonnes of proven reserves. u Burned to generate ~ 16% of Canada’s electricity (40% of global electricity production u Canada currently has 25 operating mines in 2006 u Coal industry employs 73,000 people in Canada u 70% of world’s steel is produced from coal energy - Sydney Tar Ponds, Nova Scotia u Impacts: coal burning produces the most carbon dioxide and air pollution per unit energy of all fossil fuels! Canada’s Energy Resources b) Oil – mixture of hydrocarbon compounds; most is found in sedimentary rock deep below the surface and ocean floor u Canada consumes ~ 1,665,000 barrels of oil per day u Heavy oil – shale and oil sand, found close to the Earth’s surface - Oil shale: rock that contains a solid mixture of hydrogen compounds and kerogen - Oil sand: combination of clay, water, and bitumen (e.g. northern Alberta) Petroleum products have many uses Offshore drilling produces much of our gas and oil u Drilling takes place on land and in the seafloor on the continental shelves u Platforms are either strong fixed platforms or floating platforms Primary and secondary oil extraction Alberta’s Oil Sands u Bitumenous deposits near Fort McMurray, Alberta u 2 tonnes of oil sands must be extracted, transported, an processed to produce one barrel of oil! Sydney Tar Ponds Canada’s Energy Resources c) Natural Gas – located underground, above most reserves of crude oil; gaseous hydrocarbon mixture of methane with small amounts of propane and butane u 1. Biogenic gas u 2. Thermogenic gas u 3. It can be converted to liquid Ken Saro Wiwa Ogoniland u By 2000, natural gas represented ~ 30% of Canada’s total primary energy production u Substituting natural gas for coal in electrical generation could reduce carbon emissions by 50 – 70% Enhanced Greenhouse Gas Effect Characteristics of changes in GHGs - changes in carbon dioxide: 60% if the increase has occurred since 1958 - changes in methane: largest anthropogenic sources are rice paddies, livestock enteric fermentation, biomass burning, fossil fuel production - changes in nitrous oxide: 30% of emissions related to human food production Enhanced Greenhouse Gas Effect Characteristics of changes in GHGs -changes in chlorofluorocarbons and halons: synthetic in their production - changes in aerosols: small solid or liquid particles suspended in the air, contribute to photochemical smog, acid deposition, etc. (volcanic eruptions, aircraft emissions) Smog is the most common, widespread air quality problem u Smog = unhealthy mixtures of air pollutants over urban areas u Industrial (gray air) smog = smoke plus fog n Occurs in cooler, hilly areas n Government regulations in developed countries reduced smog n Coal-burning industrializing countries face significant health risks Photochemical (brown air) smog is produced by a complex series of reactions u Light-driven reactions of primary pollutants and normal atmospheric compounds u Morning traffic exhaust releases pollutants u Irritates eyes, noses, and throats. Asthma, Bronchitis u And emphysema u Vehicle inspection programs have decreased smog Impacts of mining on the environment Habitat destruction - Open-pit mining results in the destruction of vegetation and stripping of soil. eg. Cornwall, England – Kaolin mines, - Oil/shale sand mining in Estonia. - Coal mines in the Appalachian Mountains North Dakota, Montana, Wyoming, Estevan Sask - Geological impacts : removal of soil and rocks Examples of impacts: crowholes and general subsidence. Eg. Bingham canyon in the USA Tailing ponds Accidental release of contaminants into the environment. Eg. Aznalcollar mining accident in south-west Spain. Dry contaminants When tailings dry out, winds blow dangerous compounds into surrounding environments Eg Witwatersrand, South Africa’s gold mines
