OCEAN

The term 'ocean' refers to a continuous saltwater body and its salinity determines the temperature, marine life, and other important factors in the ocean in that aspect.

Physical, chemical, as well as biological characteristics, make up some of the important features of ocean water. Each of the characteristics varies with the oceans of the world. Some of the unique attributes of the Indian Ocean, Pacific Ocean, and Atlantic Ocean are covered here and these characteristics highly impact marine life. Salinity is an important attribute as it controls evaporation, precipitation of seawater apart from temperature. High temperatures increase surface water salinity. Oceans are home to thousands of species and hence, it is important to consider their features. These unique characteristics are described here. 

Physical, chemical, and biological characteristics of Oceans

Ocean water consists of different ions such as chloride, sodium, sulphate, phosphate, and so on. About 99% of sea salts are formed by these ions. Salinity in the ocean refers to the ratio of dissolved materials’ weight and sample sea waters’ weight. This determines physical features of oceans such as temperature and it impacts marine organisms. Ocean water’s freezing point also relies on salinity. Oceans that have more saline water undergo slow freezing as compared to oceans that have less salinity. A combination of chemical as well as physical properties forms the characteristics of ocean water. Seawater’s molecular structure leads to the formation of chemical bonds among molecules. Viscosity and density of seawater also depend on salinity. The major constituents of seawater vary with different oceans due to which the temperature, density, pressure, and other physical features of oceans are different in different oceans. The major biotopes in seawater are the water column and the bottom. These are known as pelagic zones and benthic zones. Water column’s community is separated into two ecological groups, namely, plankton and nekton. 

Different characteristics of Pacific Oceans

The Pacific Ocean is the deepest ocean on the earth as compared to other oceans and is also regarded as the largest ocean. It surrounds the continents of Asia and parts of Australia and America. Several features make this ocean unique from others: 

  • The Pacific Ocean consists of highly varied topography which involves ocean ridges, trenches with long seamount chains which are developed by hotspot volcanoes found under the surface of the Earth. 

  • Its freezing point is -1.4 degrees centigrade. It has a natural depth of about 4,280 metres. 

  • Chemical, as well as biological processes, resulting in the development of metal-bearing coatings around fish ear bones and other such objects. 

  • Temperature of the Pacific Ocean has risen due to climate changes that affect marine life. In the North Pacific, the ocean temperature is higher than in the South Pacific. Different mammals such as sea otters, dugongs, various fish such as salmon, and so on survive in the Pacific ocean. 

  • Marine organisms are highly impacted by the physical features of the underwater. Growth of phytoplankton under the sea is controlled by the amount of sunlight reaching under the water. Sunlight in the sea cannot reach beyond half a mile. 

Significant features of Indian Ocean

The Indian Ocean is bounded by Pakistan, India, Bangladesh, and Iran in the North, Australia, Indonesia, Malay Peninsula, and Sunda Island in the East, Africa and the Arabian Peninsula in the west and the Southern Ocean to the south. It covers an approximately one-fifth area of the world. The annual river runoff is 2000 cubic kilometres. In the Indian Ocean, water balance is negative but in some areas such as in the Bay of Bengal, the balance is positive. 10% contribution of global marine denitrification is possible from the North Indian Ocean. Net flux of carbon dioxide from sea to atmosphere is present on the surface of Indian Ocean more than in the atmosphere. In the deepwater of the Indian Ocean, nitrogen and phosphorus are found in significant amounts. This suggests that even in great depths, organic matter oxidation is incomplete. In the deep-sea floor, the organic matter reaches as faecal pellets and in the bottom layer, it eventually gets oxidised. It has a surface circulation that is semiannually reversing. 

The Atlantic Ocean and its features

The Atlantic Ocean is regarded as the world’s second shallowest ocean. This ocean is home to different species of the earth. Some of the notable characteristics of the Atlantic ocean are:

  • This ocean has an average depth. The salinity of the ocean is about 35% but it can be as low as 25%. An increase in salinity takes place with the increase in distance from the shore. 

  • Temperature range varies from -2 degrees centigrade to 30 degrees centigrade. Surface temperature varies seasonally. 

  • Solid materials such as sodium, chlorine, calcium, magnesium, and other inorganic salts remain dissolved in the Atlantic Ocean. This ocean consists of about 96.5% of pure water and 3.5% of dissolved substances that are naturally occurring. 

  • Vertical movement of ocean water causes thermohaline circulation due to the difference in temperature and salinity. Patterns of deep ocean currents are because of thermohaline circulation. 

  • Corals, fish, mollusks, and other kinds of marine organisms are found under the seawater of the Atlantic Ocean at a depth of beyond 3,000 feet. 

Conclusion

Biological conditions are more stable in oceans than on land. Ocean is considered a stable ecosystem because of its natural liquid nature. Temperature varies with oceans and it depends on ocean salinity. Chemical components form the solid part of the ocean which are responsible for underwater salinity. Temperatures of some of the oceans are rising due to global warming and this is impacting marine life. Growth of marine organisms such as phytoplankton depends on the reach of sunlight underwater. Moreover, the physical, chemical, as well as biological features of the ocean, are the determinant factor for the survival of living organisms underwater.

faq

Frequently asked questions

Get answers to the most common queries related to the Kerala PSC Examination Preparation.

What are the fundamental biological, physical, and chemical characteristics of oceans?

Ans. Salinity, density, heat capacity and temperature are the characteristics of oceans.

What makes the Pacific Ocean unique from others?

Ans. The Pacific ocean covers more than 30% of the Earth’s surface area and is larger than all the continents combined.

What are the unique features of the Indian ocean?

Ans. The Indian Ocean covers 20% of the world’s surface area and has the lowest oxygen saturation among all the oceans.