UN Convention on the Law Of the Sea (UNCLOS)  Coastal jurisdiction 12 n. miles  Exclusive Economic Zone (EEZ) 200 n. miles  40% of ocean is under coastal control  Mineral & fishing rights  Pollution regulation responsibility  Free passage for shipping  International Seabed Authority – regulates seabed mining

EEZs of the world

EEZ of United States

Fisheries  Fish provide 15% of human protein consumption  One billion people rely on fish as their main source of animal proteins  Dependence on fish is higher in coastal areas  Some small island nations depend on fish almost exclusively  Another 35 million tons are harvested from aquaculture

Nitrogen influx is the main limiting factor Primary productivity and is very important in determining fish carrying capacity

Increasing fisheries

By-catch Species caught incidentally  Other fish species  As much as ¼ the total catch  ,000,000 tons of by-catch a year  Turtles  Seabirds (e.g. Albatrosses)  Dolphins  Tuna fishery & dolphins  Driftnets

Mariculture  37% of total world fishery  Fish  Crustaceans  Shrimp and prawn most successful  Bivalves (e.g. oysters)  Also successful  Algae  Mainly seaweeds BUT there are problems…

Mariculture  Sewage pollution  Chemical treatments  Antibiotics  Escapes of non-native species  Parasites (sea lice)  Marine mammal conflicts  Shooting seals  Acoustic Harassment Devices & cetaceans

Energy from oceans Advantages  Relatively non-polluting  Huge potential  Amount of energy available greater than fossil fuels or uranium  Renewable  Largely reliant on heat stored in oceans & atmosphere – not directly from sun  Readily available along coasts

Power from  Offshore winds  Currents – 2000 MW off Florida alone  Waves  Tides – only one being successfully exploited  Thermal energy (OTEC)

Current power

Wave power station

Potential Wave Power Hotspots

La Rance Tidal Power Plant

Potential Tidal Power Hotspots

Ocean Thermal Energy Conversion (OTEC)  Warm water near the surface heats a fluid (e.g. liquid propane or ammonia)  Liquid turns to gas – increase volume of gas turns a turbine  Cold water from the deep ocean cools down the fluid  Fluid become a liquid etc. etc.

OTEC system

Geological Resources Petroleum  95% of the economic value of non-living marine resources  Offshore about 30% of total world production (started in 1930s)  Likely to increase in future  Esp. Arctic, Asia, W. Africa & Brazil  Deeper ocean to be exploited

Geological Resources Gas Hydrates  Composed of water and natural gas (e.g. Methane hydrate)  Occur under permafrost on land and under ocean floor  High pressure and cold temperatures trap gas in water crystal lattice  Created when bacteria breakdown organic matter in seabed sediments (creating methane & some ethane & propane)

Amount of organic carbon in Earth reservoirs Other category includes peat, soil & living organisms

 Sand and gravel  2 nd to petroleum  Phosphorite (sedimentary rock)  Found at depths of <300m – usually associated with upwellings  Not currently mined but could be used to produce phosphate fertilizer  Some muds up to 18% content - also nodules (25%) Geological Resources

 Metal sulfides  Rich deposits of Cu, Pb, Zn & Ag  Found near plate boundaries  Metal enriched hot water exiting boundary meets cold seal water – sulfides precipitate  Manganese nodules  Discovered in 1872, scattered in deep ocean  Contain Mn & Fe (& Cu, Ni & Co) Geological Resources

Divergent and convergent plates and metallic sulfides

Chemical Resources Freshwater from desalination  Distillation (water vapor boiled out of seawater - but a lot of heat needed)  Electrolysis ( Na + & Cl - are removed from water by means of charged electrodes)  Reverse osmosis (water pumped in at high pressure forcing water through a semi-permeable membrane - which holds back salts etc)  Freeze separation (ice 70% lower salinity than seawater)

Reverse osmosis

Chemical Resources Evaporative salts – salts remaining when water content of seawater evaporates  Gypsum – used in plaster of Paris and gypsum board (sheet rock)  Halite – table salt

Pharmaceutical drugs  Antibiotics  Anti-inflammatory  Anti-viral  Anti-tumor  Anti-cancer