What are Ocean Resources | Ocean Resources

Ocean Resources, What are Ocean Resources, Fishing, Climate Buffer, Phytoplankton, Mining

What are Ocean Resources

The ocean is one of Earth’s most valuable natural resources. It provides food in the form of fish and shellfish. It’s use for transportation both travel and shipping. It provides a treasured source of recreation for humans. It is mine for minerals and drilled for crude oil. (What are Ocean Resources)

1. Fishing

The oceans have been fish for thousands of years and are an integral part of human society. Fish have been important to the world economy for all of these years. Fisheries of today provide about 16% of the total world’s protein with higher percentages occurring in developing nations. Marine fisheries are very important to the economy and well-being of coastal communities, providing food security, job opportunities, income and livelihoods as well as traditional cultural identity. (What are Ocean Resources)

The word fisheries refers to all of the fishing activities in the ocean, whether they are to obtain fish for the commercial fishing industry, for recreation or to obtain ornamental fish or fish oil. Fishing activities resulting in fish not used for consumption are call as industrial fisheries. Due to the relative abundance of fish on the continental shelf, fisheries are usually marine and not freshwater.

Major Fishing Grounds 

The major commercial fishing grounds are located in the cool waters of the northern hemisphere in comparatively high latitudes. Commercial fishing is little developed in the tropics or in the southern hemisphere. The best fishing grounds are there above continental shelves which are not more than 200 metres below the water surface, where plankton of all kinds are most abundant.

The world’s most extensive continental shelves are located in high or mid-latitudes in the northern hemisphere, e.g., the banks of Newfoundland, the North Sea and the continental shelf off north-western Europe, and the Sea of Japan.

Plankton are in plentiful supply in polar waters, at the meeting of cold and warm ocean currents as on the Newfoundland ‘banks’ and the Sea of Japan, or where cold water from the ocean floor wells up to the surface as it does off the west coast of South America. The continental shelves of the tropics are relatively less rich in plankton because the water is warm.

The amount of fish available in the oceans is an ever-changing number due to the effects of both natural causes and human developments.
It will be necessary to manage ocean fisheries in the coming years to make sure the number of fish caught never makes it to zero.

2. Climate Buffer

Water has a very high specific heat capacity. This means, a lot of energy is need to increase its temperature (energy is need to overcome the hydrogen bonds. As the Earth is 71% water, energy from the sun causes only small changes in the planet’s temperature. This stops the Earth getting too hot or too cold and makes conditions possible for life. Heat gets store by the ocean in summer and release back to the atmosphere in winter. Oceans, therefore, moderate climate by reducing the temperature differences between seasons.

By far the largest carbon store on Earth is in sediments, both on land and in the oceans, and it is held mainly as calcium carbonate. The second biggest store is the deep ocean where carbon occurs mostly as dissolved carbonate and hydrogen carbonate ions. About a third of the carbon dioxide from fossil fuel burning is stored in the oceans and it enters by both physical and biological processes.

3. Phytoplankton

Phytoplankton accounts for around 90% of the world’s oxygen production because water covers about 70% of the Earth and are abundant in the photic zone of the surface layers. Some of the oxygen produced by phytoplankton is absorbed by the ocean, but most flows into the atmosphere where it becomes available for oxygen dependent life forms.

4. Mining

The oceans hold a veritable treasure trove of valuable resources. Sand and gravel, oil and gas have been extracted from the sea for many years. In addition, minerals transported by erosion from the continents to the coastal areas are mined from the shallow shelf and beach areas. These include diamonds off the coasts of South Africa and Namibia as well as deposits of tin, titanium and gold along the shores of Africa, Asia and South America.

Natural gas and oil have been extracted from the seas for decades, but the ores and mineral deposits on the sea floor have attracted little interest. Yet as resource prices rise, so too does the appeal of ocean mining.

Deep Sea Mining

Back in the early 1980s there was great commercial interest in marine mining. This initial euphoria over marine mining led to the International Seabed Authority (ISA) being established in Jamaica, and the United Nations Convention on the Law of the Sea (UNCLOS) being signed in 1982 – the “constitution for the seas”. Since entering into force in 1994, this major convention has formed the basis for signatories’ legal rights to use the marine resources on the sea floor outside national territorial waters.

After that, however, the industrial countries lost interest in resources. For one thing, prices dropped making it no longer profitable to retrieve the accretions from the deep sea and utilize the metals they contained. Also, new onshore deposits were discover, which were cheaper to exploit.

The sharp increase in resource prices and attendant rise in profitability of the exploration business.
Strong economic growth in countries like China and India which purchase large quantities of metal on world markets. Even the latest economic crisis is not expect to slow this trend for long.
The industrial and emerging countries’ geopolitical interests in safeguarding their supplies of resources also play a role. In light of the increasing demand for resources, those countries which have no reserves of their own are seeking to assert extraterritorial claims in the oceans.

Major Deep Sea Minerals

The major focus is on manganese nodules, which are usually located at depths below 4000 metres, gas hydrates (located between 350 and 5000 metres), and cobalt crusts along the flanks of undersea mountain ranges (between 1000 and 3000 metres), as well as massive sulphides and the sulphide muds that form in areas of volcanic activity near the plate boundaries, at depths of 500 to 4000 metres.

(a) Manganese Nodules

Manganese nodules are lumps of minerals covering huge areas of the deep sea with masses of up to 75 kilograms per square metre. Manganese nodules are compose primarily of manganese and iron. The elements of economic interest, including cobalt, copper and nickel, are present in lower concentrations and make up a total of around 3.0 per cent by weight. In addition there are traces of other significant elements such as platinum or tellurium that are important in industry for various high-tech products.

These chemical elements are precipitate from seawater or originate in the pore waters of the underlying sediments. The greatest densities of nodules occur off the west coast of Mexico, in the Peru Basin, and the Indian Ocean.

(b) Cobalt crusts

These crusts accumulate when manganese, iron and a wide array of trace metals. Get dissolved in the water (cobalt, copper, nickel, and platinum). The cobalt crusts also contain relatively small amounts of the economically important resources. Extracting cobalt from the ocean is of particular interest. It is because it is on land in only a few countries (Congo, Zaire, Russia, Australia and China). Some of which are politically unstable.

Cobalt crusts form at depths of 1000 to 3000 metres on the flanks of submarine volcanoes. Therefore usually occur in regions with high volcanic activity such as the territorial waters around the island states of the South Pacific.

(c) Massive Sulphides

Sulphur deposits produce from underwater volcanic areas are call as black smokers. These occurrences of massive sulphides form at submarine plate boundaries, where an exchange of heat and elements occurs between rocks in the Earth’s crust and the ocean due to the interaction of volcanic activity with seawater. Cold seawater penetrates through cracks in the sea floor down to depths of several kilometres. Near heat sources such as magma chambers, the seawater is heat to temperatures exceeding 400 degrees Celsius.

Upon warming, the water rises rapidly again and is extrude back into the sea. These hydrothermal solutions transport metals dissolve from the rocks and magma. Which are then deposit on the sea floor and accumulate in layers. This is how the massive sulphides and the characteristic chimneys (black smokers) are produce. So far only a few massive sulphide occurrences which are of economic interest due to their size and composition are known. (What are Ocean Resources)

While the black smokers along the East Pacific Rise and in the central Atlantic produce sulphides. Comprising predominantly iron rich sulphur compounds. Which are not worth considering for deep-sea mining. The occurrences in the southwest Pacific contain greater amounts of copper, zinc and gold. The largest known sulphide occurrence is in the Red Sea. Here, the sulphides are not associate with black smokers, but appear in the form of iron rich ore muds.

Constraints in Deep Sea mining

The most limiting factors associated with deep-sea marine mining are the political and legal aspects. Legal and political issues surrounding exploration, exploitation, and marketing of sea floor minerals must be resolve.
–  The excavation of marine minerals disturb parts of the seabed. Huge amounts of sediment, water, and countless organisms dug up with the nodules, and the destruction of the deep-sea habitat  be substantial. It is not yet known how, or even whether, repopulation of the excavated areas would occur.
Sea floor mining will only be able to compete with the substantial deposits presently available on land if there is sufficient demand and metal prices are correspondingly high.
The excavation technology has yet to be develop. There are serious technological difficulties in separating the crusts from the substrate.  Which combined with the problems presented by the uneven sea floor surface. Further reduce the economic potential of the marine mining.

Despite the challenges, deep sea mining has some potential benefits over terrestrial mining:

–  The minerals are often much closer to the surface, so operations have to dig and displace less rock, meaning a smaller footprint and fewer carbon emissions.
–  Seabed mining infrastructure is both moveable and reusable, unlike roads and buildings often left behind at abandoned mines on land.
And no residents will be directly displace by mining.

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