The planet earth is believed to have come about through the collision of a giant disc-shaped cloud of materials that resulted in the formation of the planets and the sun (Stanley, 2005). Gravity mixed "gas and dust" to form asteroids and small planets which later became bigger due to repeatedly collision, thus, building up the planets in solar system. When earth started to cool, its surfaces solidified, and water vapor surrounded it. The water vapor condensed into liquid and fell into the hollows of the earth surface forming oceans. The forces of gravity prevented the water formed in the hollows of the earth from leaving the planet. The earth is composed of four major layers namely, core, mantle, asthenosphere, and lithosphere. The core contains "Nickel and Iron; Mantle contains molten rock called magma; asthenosphere contains semi-molten ductile rock while lithosphere contains solid upper mantle” (Stanley, 2005). Mantle is the part of the earth that is below the crust, and it surrounds the outer core. Mantle contains the most significant volume compared to the rest three layers of the planet. The core, on the other hand, is made up of molten or liquid shell below the mantle that encircles Earth's inner core.
The knowledge about how the composition of mantle and core comes from seismic and petrological studies. Critical information is obtained from geochemical studies on the meteorite and lunar samples. Seismic surveys give information about density. With the help of experimental petrological studies, the structure of mantle minerals and rocks is easy to find. Scientists study the seismic data, rock samples from mantle and core to determinate the composition of the two layers of the earth. The mantle is made of rock, which we know from chemical analysis of samples from upper mantle material that is ejected occasionally from volcanoes. The structure, density, and size of the core can be determined by analyzing the seismic waves traveling through Earth's interior. Based on our understanding of planetary formation, internal differentiation, the calculated density of the core, and the relative abundances of chemical elements in the solar system, scientists conclude that the core consists of heavy elements. The elements residing in the core are primarily, but not limited to, iron and nickel.
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The tragedy of the commons refers to the destruction that is caused by people in the resources owned commonly or holds jointly. Every person develops self-interest to deplete the resources, thus, undermining the collective interest by over-exploiting the resources instead of protecting them (Angus, 2008). The tragedy of over-exploiting the resources that are owned commonly is causing damage to resources that cover the surfaces of the earth such as oceans. The high seas refer to the area of the ocean that is located beyond coastal states that is common to all. Fishing in this area is open to all people, and any mineral found in this area can be exploited by all (Hardin, 2008). Therefore, people tend to over-exploit resources found in high seas causing damage to oceans and seas. People have abused the ocean-commons through over-fishing in high seas which is common to all leading to a reduction of numbers of fishes in the sea. Again, people tend to dump waste materials and plastics in ocean-commons thus polluting the environment.
Many high seas fisheries lack protection or any policy that regulates the extent of fishing in high seas. Many people over-exploit resources on high seas with the explicit knowledge that that is damaging what they ought to protect. The high seas and ocean have not been spared in climate change. The industries direct their waste which is not treated to ocean water thus, adding carbon dioxide and aerosol in the ocean water increasing ocean acidity. As Ron Dunbar noted in the film; ‘discovering ancient climates in the ocean and ice,' circulating current gather floating waste such as plastics creating ocean garbage patches (Talks, 2012). Climate change is reducing the amount of water in the ocean. Global warming is heating the surface ocean, reducing the amount of oxygen in the deeper waters. There is a need to develop high seas laws that will regulate the use of the shared resource to prevent their over-exploitation.
References
Angus, I. (2008). The myth of the tragedy of the commons. Socialist Voice .
Hardin, G. (2008). "Tragedy of the Commons". In David R. Henderson. Concise Encyclopedia of Economics (2nd ed.). Indianapolis: Library of Economics and Liberty .
Stanley, S. M. (2005). Earth system history (2nd ed.). . New York: Freeman. ISBN 978-0-7167-3907-4.
Talks, T. (2012). Podcast: TED Talks series - Rob Dunbar: Discovering Ancient Climates in Oceans and Ice.
