why study oceanography? a few answers. why study oceanography? oceans are still a frontier –much...
Post on 21-Dec-2015
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WHY STUDY OCEANOGRAPHY?
A Few Answers
Why Study Oceanography?• Oceans are still a frontier
– Much research needed– Compare to surface of Moon
• Major food source – Nova Scotia Fisheries: ~7 000 jobs,
~$400 M wages, ~$400 M product value
• Recreation (especially coastal regions)• Mineral sources
– Sand & gravel– Manganese nodules– Other minerals
• Energy source (ca. 30% of oil & gas – offshore drilling & production from manmade platforms) (+40% for USA)
Why Study Oceanography?
• Canadian Offshore Petroleum Resources– Scotian Shelf (gas & oil)
• Venture gas discovered 1979– Producing today, pipline system
• Cohasset oil production 1992– Grand Banks (oil)
• Hibernia giant oil field 1979• Production began in 1998!
– Beaufort Sea (oil)• Amauligak giant oil field 1986
– Labrador Shelf (gas known – severe iceberg/climate problems)– Baffin Island Shelf (reasonable hope for oil/gas)– Canadian Arctic islands (oil & gas known – climate factor)– British Columbia Shelf (hopes)
Why Study Oceanography?• Discovery of plate tectonics in ocean basins has
revolutionized our view of Planet Earth
• Oceans greatly influence our weather & climate because of high heat capacity of water• Transportation – still an important means of human travel
Why Study Oceanography? • About 90% of intercontinental trade is by marine shipping
– For example, chart below shows the major crude oil sea distribution routes
Oil Tanker
Why Study Oceanography?
• 71% of Earth’s surface is covered by the oceans• Pollution (waste disposal problems & abuse)• Communication (e. g., undersea cables)• Hazards (coastal, shelf, open ocean, deep-sea)• Military uses (e. g., national defense) • Coastal Zone
– Environmentally diverse
– Multiple use management
– Erosion and pollution control problems
– Overpopulated
• Salt source (evaporation)• Water source (desalination)
Why Study Oceanography?• Source of water for Earth’s water cycle
• Oceans are the destination of continental water (& sediment) runoff.
Why Study Oceanography?
• Destination of continental sediments– ca. 90% of all sediments are marine:
• Continental shelves = 15%
• Continental slopes = 40%
• Continental rises = 25%
– Sediment transport agents• Ice (glaciers), wind (dunes), water (rivers, marginal seas)
• Sea-level changes (due to ice ages)
Why Study Oceanography?
• Major role in geologic history of Earth– Continental drift, seafloor spreading, magmatic arcs
• Canada borders three oceans– Atlantic
– Pacific
– Arctic
• Canada Has the Longest Coastline – Atlantic:
• 45,000 km long 19% of Canadian coastline
– Pacific:• 26,000 km long 11% of Canadian coastline
– Arctic:• 173,000 km long 71% of Canadian coastline
19%
11%
71%
Why Study Oceanography?• Political and legal problems:
– NS & NF are in a dispute over their offshore boundary– Canada’s 200 nt mile fishing zone declared in 1977– Not all countries signed 1982 Law of the Sea Treaty – USA-Canada Eastern boundary dispute
• Gulf of Maine-Georges Bank
• Alaska-BC offshore boundary
• “NW passage”
– Smuggling along remote coasts– Arctic sovereignty (ownership?)– France-Canada
• Grand Banks dispute
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