We must change our way with the sea. There is a possibility of a catastrophe. More than half the people in the world lives within 100 kms of the sea. There is mounting evidence that it is adversely affected by human activity. The fish is going, and other sea creatures are suffering.
Hauling large nets over the seabed to catch fish disturbs the environment. Coral reefs are being reduced, water temperatures are increasing, the water level rises, about a third of the CO2 emissions are taken up by the sea making it more acid, changing the habitat of many organisms and killing some of them. The food chains are thus being changed with many consequences, most of them bad.
We throw rubbish into the sea with many chemicals, metals and new species. This causes problems of many kinds and also algae blooming.
A scramble for the seabed is coming, and an UN International Seabed Authority has been set up. Interests range from mining, oil, gas hydrates, new sealife discoveries, black smokers – vents – with newfound creatures finding food from the earth.
About a third of the carbon ends up in the sea in the processes of the sea flows. The increase in CO2 has made the sea more acid. This has consequences, but no one really knows what.
The London dumping convention was signed in 1972, but the dumping is far too high: oil spills, medical waste, metals, radioactive effluent, plastic, toxic chemicals causing chest and lung diseases along coasts. Slime is growing too.
The rate at which CO2 is absorbed by the sea can be speeded up by adding iron. The consequences are not clear.
It could also be possible to capture CO2 and store it under the sea. This idea is not well developed.
Windmills, tidal and wave power have potential and are being tested.
Modern technology has greatly affected fisheries and made overfishing easy. The regulatory mechanisms are not good or have failed completely, but an example from Iceland with trade of quotas, good registration and controls, including transparency, shows the way.
Fish farming is an important factor as large amounts of “lesser” fish are caught to feed the fish in the farms. These fish may be ecologically valuable so care should be taken. The farmed fish should be ecologically neutral?
Natural plant eaters like shells should be considered for farming. They may even clean the water.
The sea needs attention in the form of research, management, property rights and international political cooperation. The ownership and responsibility of the seas must be established and controlled internationally.
Pew Oceans Commission http://www.pewtrusts.org/ produces policy recommendations.
