General Information:

The Atlantic Ocean stretches more than 41 million square miles. It is the second largest ocean on Earth after the Pacific Ocean. The Atlantic covers one-fifth of Earth’s surface. It separates the continents of Europe and Africa to the east.  North and South America lie to the west of the Atlantic Ocean. Although it is not the largest ocean in the world, it has by far the largest drainage area. The continents on either side of the Atlantic slope inward towards the ocean, meaning that a majority of the world's river's flow directly into the Atlantic.  It also has an average depth of 27,493 feet which is home to a variety of different sea life. Some that can be seen by the naked eye, and some that are hidden from our eyes. This includes: lobster, haddock, cod, mackerel, herring, menhaden, sea scallops, shrimp, and many others. A major feature of the Atlantic that stands out is the Mid-Atlantic Ridge. This is an immense median mountain range that extends throughout the length of the Atlantic, reaching roughly 1000 miles (Britannica).

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The Atlantic Ocean’s origin is centered around different theories on plate tectonics and the continental shift. “The Pangea, an ancient supercontinent, began rifting about 180 million years ago. The rifting causes the Eastern and Western Hemisphere to drift apart, leading to the Atlantic Ocean Basin Information” (WorldAtlas). This body of water covers about one fifth of the Earth’s surface. Also known as the “Sea of Atlas”, it covers about “41.1 million square miles or 20 % of the Earth’s total area” (WorldAtlas). 

The main features of the Atlantic Ocean include bays, seas, and gulfs.  A bay is a broad, recessed coastal inlet where the land curves inward. However, a gulf is deeper and more defined inlet with an entrance more secluded than a bay. The largest sea in the Atlantic is the Sargasso Sea. It spans over 1.35 million square miles. The second largest sea is the Caribbean Sea which spans 1.1 million square mile. The other seas in the Atlantic Ocean are  the Argentine Sea, Greenland Sea, Hudson Bay, Norwegian Sea, Gulf of Mexico, Gulf of Guinea, and the Mediterranean Sea. 

There are a lot of different factors that affect the Atlantic Oceans climate. There is a lot of wind, water currents, and surface water temperature. The North Atlantic weather is mainly determined by the amount of air mass and wind current originating from North America (World Atlas). 

The Atlantic Ocean is home to a lot of different sea creatures. However, a set of them are actually in danger. These species are sea turtles, whales, and manatees (World Atlas). Crabs, sea lions, catfish, starfish, gray Atlantic seals, shrimps, octopi, penguins, sharks, and all kinds of different animals are found in this ocean. The coral reefs present here are also home to an array of fish and other marine animals, as well as plants.

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General Information

The Pacific Ocean is the largest ocean on the planet, covering over a third of the earth’s surface. It is approximately 161.76 million square kilometers (about twice the area of the Atlantic Ocean) and 62.5 million square miles. “To get a sense of just how immense the Pacific Ocean is, you could put all of Earth's landmasses together, and the Pacific would still be larger” (1). It is located between the western coast of North and South America and extends to the coast of Asia. The Pacific is the deepest ocean with the average depth being 14,040 ft deep, and the deepest part of the ocean being 36,201 ft deep, located in the Mariana Trench (Morgan et al 2021). 

The Pacific Ocean didn’t just get its name from anybody. A man by the name Ferdinand Magellan named it in 1520 as he sailed through it. To take in perspective how big the Pacific Ocean is, “It has double the area and double the water volume of the Atlantic Ocean” (Britannica). It is also divided into three major physiographic regions. These regions are the eastern, western, and central Pacific regions.

The Pacific Ocean evolved a very long time ago. It evolved in the Mesozoic from the Panthalassic Ocean. It reportedly was formed when Rodina drifted apart around 750 Ma. “The first ocean floor ascribed to the current Pacific plate was produced to the west of a spreading in the central pacific” (TRS).  

The Pacific is the deepest ocean with the average depth being 14,040 ft deep, and the deepest part of the ocean being 36,201 ft deep, located in the Mariana Trench (Morgan et al 2021). It covers one third of the world! It stretches from the Bering Strait to Antartica, which extends for 9,600 miles (Britannica). The Pacific Basin is divided into three major regions the eastern, western, and central regions (Britannica).

The Pacific Ocean is not just an ordinary body of water. The Pacific can bring about some very intense hurricanes. A storm called Super Typhoon Mangkhut was a very strong storm in 2018. It hit the Philippines before completely taking out the mainland in China. “At its strongest, the storm’s winds topped 165 miles per hour, uprooting trees, destroying homes, and causing deadly mudslides” (National Geographic). The Pacific also has the “Ring of Fire.” The reason why they have this is because of the volcanic and earthquake activity towards the edges of the Pacific. “The resulting chain is roughly 25,000 miles long and springs to life where the Pacific tectonic plate slides against or collides into the other tectonic plates that circle it” (National Geographic). It also has the Mariana Trench, which is a deep ocean trench that sits along the Ring of Fire. 

The Pacific has the most varied array of plants and animals of the world’s oceans. In the warm tropical region between the North and South Equatorial Current systems, the shear amount of varying marine life increases dramatically. This variation is greatest in the western Pacific, which has the richest and most extensive coral reefs of any ocean. In fact, there are six times more species of fish associated with them than with the coral reefs of the Caribbean Sea in the Atlantic (Britannica)

The origins of the Indian ocean are the most complicated of all the major oceans. Studies show that the formation was caused by the breakup of the supercontinents about 180 million years ago as a result of tectonic plate movement. According to Britannica, the break-up of the southern supercontinent Gondwana (or Gondwanaland)beginning about 125 million years ago, collided with Eurasia about 50 million years ago. Eventually, with the western movement of Africa and separation of Australia from Antarctica, the Indian Ocean had taken on its present configuration. Interestingly, almost all of the Indian Ocean basin is less than 80 million years old, compared to the Pacific and Atlantic which are between 145-180 million years old (Britannica). 

Oceanic Ridges

Beneath the surface of the world's oceans, there is an oceanic ridge system forming what we know as the seafloor. These ridges merge between oceans and continents, and are often seismically active. However, one of the most interesting ridges lies beneath the Indian Ocean, where the “aseismic” (virtually earthquake-free) Ninetyeast Ridge, which is the longest and straightest in the world ocean lies (Britannica). The ridge runs north-south essentially the entire north-south span of the Indian Ocean. 

Bottom Deposits

Suspended sediments (accumulation of rock, debris, and other material) from the many rivers that empty into the Indian Ocean is the highest of the three major oceans. According to Britannica, nearly half of the Indian Ocean’s sediment deposits come from the Indian subcontinent alone (Britannica). Although, not much of the sediment accumulates in some areas because of the Java Trench, acting as a sediment trap.

Monsoons

The Indian Ocean is known for its extensive monsoon season. As winter ends, warm, moist air from the southwest blows towards countries like India, Sri Lanka, Bangladesh, and Myanmar. The summer monsoon brings a humid climate and torrential rainfall to these areas from May to October. Destructive tropical cyclones are known to form over the open ocean and migrate to the western countries bordering the ocean. One such storm, the Ganges-Brahmaputra cyclone, killed hundreds of thousands of people in 1970.

Trenches

Trenches are products converging tectonic plates, which create deep, long narrow depressions on the seafloor. These chasms are some of the deepest natural locations on Earth. The Indian Ocean has the fewest trenches in the world, although the seismically active Java Trench is the world’s second longest trench, stretching more than 2,800 miles from southwest of Java. The northern portion of the trench was responsible for a massive undersea earthquake in 2004 (magnitude 9.1), affecting nearly 600 miles and causing a series of devastating tsunamis in Indonesia (Britannica). 

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General Information

The Southern Ocean, or the Antarctic Ocean covers only 1/16 of the Earth’s oceans, but is still considered part of the seven seas with a coverage of about 8 million square miles. In reality, it is a culmination of the world’s major oceans at the southern tip of the globe, including the Pacific, Atlantic, and Indian oceans. Other than Antarctica, the ocean is uninterrupted by any other land masses. The Southern Ocean has an average depth of 10,728 feet, with its deepest point being 24,383 feet deep.

The origins of the Indian ocean are the most complicated of all the major oceans. Studies show that the formation was caused by the breakup of the supercontinents about 180 million years ago as a result of tectonic plate movement. According to Britannica, the break-up of the southern supercontinent Gondwana (or Gondwanaland)beginning about 125 million years ago, collided with Eurasia about 50 million years ago. Eventually, with the western movement of Africa and separation of Australia from Antarctica, the Indian Ocean had taken on its present configuration. Interestingly, almost all of the Indian Ocean basin is less than 80 million years old, compared to the Pacific and Atlantic which are between 145-180 million years old (Britannica). 

The Southern Ocean is full of narrow oceanic trenches, oceanic plateaus, oceanic basins, and more. The southern Antarctic ocean is quite unique with its landforms because of its geographic location, being a sedimentary deposit site for much of the world’s oceans.

The flow of currents through the Southern Ocean is complex. The water is cooled by cold air, outgoing radiation, and katabatic winds -also called downslope wind, is wind that blows down a slope because of gravity. It occurs at night, when the bordering continents radiate heat and are cooled. These winds from the Antarctic continent sink and flow northward along the ocean bottom, and is replaced at the surface by an equal volume of warmer water flowing south from the Indian, Pacific, and Atlantic oceans. The meeting point of the two is the Antarctic Convergence.

Bottom Feeders

Majority of other organisms living in the Antarctic are bottom feeders, thriving in one of the most uninhabitable environments, evolving to live in dark, freezing conditions. Animals like starfish, crustaceans, mollusks, sponges, and isopods thrive the most here. 

Phytoplankton

The Southern Ocean currents and Antarctic Convergence favor the development of phytoplankton.

Why are phytoplankton important? They are the ocean’s most important organism in tandem with the world’s food chain. Oceanic phytoplankton is the primary food source, directly or indirectly, of nearly all sea organisms (Britannica), essentially acting as the foundation for the world's food chain.

The accepted theory for the Arctic Ocean’s formation is based on the theory of seafloor spreading, which explains that the oceanic crust was formed along submarine mountain zones, or the mid-ocean ridge system, and spread away from there. Thus, the focus of this spreading began under the Asian continent ridge line.

The sediment deposits on the ocean floor are what allow researchers to date these developments, looking deep into the ocean's crust. This research is crucial for understanding how the oceans were formed and developed and for understanding the relevance towards global environmental and climatic changes.

Overall Makeup

Originally, in its first discovery, the Arctic was thought to be one large basin. Until about 1950, this was the accepted theory. However, scientists soon learned that the Arctic Ocean consists of two primary deep basins which are then subdivided into four smaller basins by three transoceanic ridges (Britannica).

Ridges/Mountains

The Lomonosov Ridge, an enormous submarine mountain range extends from the continental shelf of Ellesmere Island to the New Siberian Islands, which covers roughly 1100 miles. The ridge essentially divides the Arctic ocean in two, or the two primary basins because of the ridge’s difference in height of 10,000 feet. One side is known as the Eurasia Basin on the European side of the ridge and the Amerasian Basin on the American side. 

Continental Shelf 

The Arctic Ocean is unique in that ⅓ of its total area is considered a continental shelf, or a portion of a continent which is entirely submerged underwater. This includes portions of northern Alaska and Greenland, where the shelf is only 60 to 120 miles wide, and the Siberian and Chukchi shelves off Eurasia, ranging from 300 to 1,100 miles in width (Britannica).