The ocean gyres have 17 characteristics, the 17 characteristics of ocean gyres could you find it here. So, what is ocean gyres? Ocean gyre is a large system of a circular ocean, and ocean gyre is created by global winds and Earth’s rotation. These currents are apart of the Coriolis Effect. The 17 characteristics of ocean gyres are different in each location, circulation and also the types of gyres. We will inform you all, here and it will start from.
Coriolis Effect and Ekman Transports
The Coriolis effect is an effect which it’s moving in a rotating system experiences a force acting perpendicular to the direction of motion and to the axis of rotation. It tends to deflect moving objects to the right in the northern hemisphere and to the left in the southern.
Besides the Ekman Transport is the net transport of water between wind and surface waters. The direction is dependent oh the hemisphere; like in the northern, it transports occur at 90 degrees clockwise from the wind direction and the southern hemisphere it occurs at 90 degrees counterclockwise. Ekman spiral is a complex interaction on the surface of the sea between wind, rotation of earth and friction forces by Vagn Walfrid Ekman.
Types of Ocean Gyres
There are five major of location in ocean gyres; North Atlantic, North Pacific, South Atlantic, South Pacific, and India gyres. Each of this location has different types and boundary current. Below these are the explanation.
Tropical gyre is located near the equator, so in here the Coriolis effect not present here. The wind in tropical gyre is a primary creator of currents.The example of tropical gyre is Indian Monsoon gyres. The Indian Monsoon current is kind of ocean currents, you can check also in Impact of Ocean Currents. It found in the tropical regions of the northern Indian ocean.
During the summer, the direction reverses, it flows eastward extending from Somalia into.the Bay of Bengal. These variations are due to changes in the wind stress associated with the Indian monsoon. The Somali current, it flows along the Horn of Africa and it also shifts direction seasonally with the monsoon winds. It separates from the coastline, and it turns as right as it enters the Arabian Sea.
This current is located between 10 and 15 North latitude in the Arabian sea, bends around India and Sri Langka and also enters the Bay of Bengal. The Great Whirl is only present during the summer season.
2. Sub Tropical
Subtropical is located in the polar regions of the planet, it beneath an area of low atmospheric pressure. The wind also drives currents away from coastal areas. South Atlantic gyre is the one of the major location of this type. The Southern boundary, the wind drives eastward that are difficult to distinguish from the northern boundary of the Antartic.
This gyre flows from West to the East around Antartica to maintain its huge ice sheet by keeping warm ocean away, and it called West Wind Drift. This gyre is the largest ocean current. Besides the western boundary, it flows along the Brazilian coast to the Rio de la Plata (Brazilian Current). Another major location that of this type is Indian ocean gyre. It primarily between the South Equatorial Current and the West Australia current. It borders Australia, Africa, and Asia and it also moves counterclockwise due to the Coriolis Effect.
The Indian ocean gyre is in a remote area, the study for the Indian ocean gyre is really varied. It was discovered in 2010 by the marine biologist and founder of the organization, Marcus Eriksen. The Indian gyre typically travels from west Australia towards east Africa in which that wash ashore end up on the beaches of Madagascar.
3. Sub Polar
The subpolar is the smaller than subtropical, they are in the Alaska gyre in the far North Pacific and the gyre south of Greenland in the far North Atlantic. The counterclockwise surface winds in the Aleutian and Icelandic sub-polar lows drive the sub-polar gyres.The rotation of this polar is opposite that the Northen Hemisphere subtropical gyres. The subpolar forms between the polar and equatorial regions of Earth. The circle areas beneath regions of high atmospheric pressure.
Water generally stays in place while the gyre currents circulate around it. The subpolar gyre finds in the North Pacific. It composed of the northward-flowing Alaska current, the Surbasrtic current, and the southward-flowing cold Oyashio current. Besides the subpolar gyre in the North Atlantic, it does not only affect the climate of the North Atlantic and Europe, but also the rainfall which it places at the Sahel in Africa, Amazon and some parts of the US.
4. Western Boundaries
In the western boundaries, there are three currents that we found here; The gulf stream, The Japan Current, and Brazil Current.
a. The Gulf Stream
Powerful current in the Atlantic ocean, it flows together with North Atlantic Gyre. It’s warm and from the Gulf of Mexico and flows into the Atlantic at the tip of Florida., accelerating along the eastern coastlines of the U.S. and Newfoundland.
Gulf Stream is apart of the North Atlantic with types Subtropical Gyre. It is the large systems of circular currents and powerful winds. It is a western boundary because it’s behavior determined by the North American coastline.
Tradewinds from Africa drive water to the Atlantic westward until it hits the coastline and it pushed away to northward.
b. Kuroshio Current
Besides, the Japan current or we are known as Kuroshio Current, it’s similar to the Gulf stream. This current is a subtropical gyre and it begins off the east coast of Luzon, Philippines, Taiwan and flows northeastward to Japan. It merges easterly with a drift of the North Pacific current.
Kuroshio current is a warm current, this western boundary currents transport organisms long distances rapidly and various marine organisms migrate in this current.
c. Brazil Current
The last is Brazil Current, it is the weakest western boundary current among others. It runs along the coast of Brazil and it’s generally confined to the upper 600m of the water column. It flows southward in the South Atlantic ocean along the eastern coast of South America and then Brazil. This current is characterized by warm temperatures that vary and a high salinity. It surfaces speed of one to two knots and a depth of 100-200 meters.
5. Eastern Boundaries
Eastern boundaries, there are three currents that we found here same like the western boundaries. They are California current, Peru current, and Benguela current.
a. California Current
The California current flows continuation of the Aleutian current along the west coast of North America.The velocity is commonly less than 25 c, per second. It transports about 11,000,000 cu m of water. The temperature and salinity of this current it varies with variations in upwelling, insolation, and flow.
b. Peru / Humbold Current
Next, the Peru Current or also called with Humboldt Current. It is a cold water current of the southeast Pacific Ocean. This current similar to the Californian current of the North Pacific.
It flows east toward South America and it continues through the Drake Passage around the southern tip of South America to the Atlantic. The shallow stream turns north to the continent while it turns west it joins to the Pacific South Equatorial current. Humboldt current is a cold current, it brings fog to the nearby coast.
This cold flow is intensified by upwelling of deep water and it brings nutrients close to the surface and the beneficial effects of sunlight.
c. Benguela Current
The last of east boundary is Benguela Current, it forms the eastern part of the Southern Atlantic Ocean gyre. This stream is the current northward in the South Atlantic Ocean along the south-west coast Africa. Benguela’s current sources include the Atlantic of India and the South subtropical thermocline water; salt, low water oxygen tropical and cold Atlantic water fresher subantarctic water.
This current has a flow that is mostly limited in close proximity continents and transient currents are more varied The west side of the stream is dominated by a large swirl that is shed from Agulhas Retrofleksi, Barotropic, and baroclinic components. The coldest waters of the current flow right along the coast of Africa, with very small seasonal variations except in the extreme south near Cape Town, South Africa, where the water is colder in summer than in winter.
Gyres and Ocean Garbage Patches
All of the gyres in our ocean that always bring garbage. How is it work? Below here the major of the location of the gyre and the relation of garbage patches.The North Atlantic Gyre is located in the Atlantic ocean. It forms the Sargasso Sea, noted for its still water and dense seaweed accumulations. There is a damage caused by the gyre is catastrophic.
The sea creatures eat all the marine debris which causes them die, which it affects the entire food chain in the ocean. When the fishes are eating the marine debris such as plastics and they die, bigger fish eat them and die from the marine debris and the cycle continues until everything dies. The North Atlantic garbage patch is an area of man made this marine debris and it was found floating since in 1972. There is approximately 56.5 thousand tons of plastic found in the North Atlantic now.
Besides now we look after to the North and Pacific Gyre, The facts about the Great Pacific ocean weather in North and south are it founds 7 million ton of weight from marine debris. The size is twice than Texas. It is up to 9 feets deep. In this gyre, there is 6 times more plastic found than plankton which is the main food for many ocean animals. The marine debris estimation of 80 percents are plastic, it originates from land.
It floats on the rivers to the ocean or blowing by the wind to the ocean. The others remaining of 20 percents are from oil platforms and cruise ship. The scientific researchers in California show that 5 to 10% of our fishes contains plastic. And others like in the Indian and South Atlantic are bringing the garbage patches too.
This problem must be taken seriously, you know over 268,000 tons of trash and plastics floating in the world’s ocean. Various marine life eating the debris as food and ultimately die from it.Besides it threat to the ocean organisms and ecosystem that can be destroyed.This effect will get we as human when the humans eat affected fish, it can be passed along to us and it will make our health in danger. As human we must consider this thing seriously, we can reuse, recycle and reduce the marine debris as well. So, our ocean will safe. Hopefully, this article can useful for you who want to know about the 17 characteristics of ocean gyres.
See Also :
- Characteristics of Oceanic Plates
- Characteristics of an Ocean Ridge
- Impacts of Ocean Currents on Climate