why do ocean currents generally originate near the equator?

Dear Student,
Ocean currents are responsible for regulating the earths climate.
They transfer the heat from the warm tropical areas to the colder areas near the poles.

Areas near the equator receive more direct solar radiation than areas near the poles. However,these areas do not constantly get warmer and warmer. The reason is that the ocean currents & winds transport the heat from the lower latitudes near the equator to higher latitudes near the poles. And this is also the reason why the currents originate near the equator.

Hope this helps.
Regards
Jaya TIwari

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Primary Forces Responsible For Ocean Currents Explain the factors responsible for the origin of ocean currents. How do they influence regional climates, fishing and navigation? [Mains 2015] Influence of insolation

Heating by solar energy causes the water to expand. That is why, near the equator the ocean water is about 8 cm higher in level than in the middle latitudes.
This causes a very slight gradient and water tends to flow down the slope. The flow is normally from east to west.

Influence of wind (atmospheric circulation)

Wind blowing on the surface of the ocean pushes the water to move. Friction between the wind and the water surface affects the movement of the water body in its course.
Winds are responsible for both magnitude and direction [Coriolis force also affects direction] of the ocean currents. Example: Monsoon winds are responsible for the seasonal reversal of ocean currents in the Indian ocean.
The oceanic circulation pattern roughly corresponds to the earth’s atmospheric circulation pattern.
The air circulation over the oceans in the middle latitudes is mainly anticyclonic [Sub-tropical High Pressure Belt] (more pronounced in the southern hemisphere than in the northern hemisphere due to differences in the extent of landmass). The oceanic circulation pattern also corresponds with the same.
At higher latitudes, where the wind flow is mostly cyclonic [Sub-polar Low Pressure Belt], the oceanic circulation follows this pattern.
In regions of pronounced monsoonal flow [Northern Indian Ocean], the monsoon winds influence the current movements which change directions according to seasons.

Influence of gravity

Gravity tends to pull the water down to pile and create gradient variation.

Influence of Coriolis force

The Coriolis force intervenes and causes the water to move to the right in the northern hemisphere and to the left in the southern hemisphere.
These large accumulations of water and the flow around them are called Gyres.These produce large circular currents in all the ocean basins. One such circular current is the Sargasso Sea.

Secondary Forces Responsible For Ocean Currents

Temperature difference and salinity difference are the secondary forces.
Differences in water density affect vertical mobility of ocean currents (vertical currents).
Water with high salinity is denser than water with low salinity and in the same way cold water is denser than warm water.
Denser water tends to sink, while relatively lighter water tends to rise.
Cold-water ocean currents occur when the cold water at the poles sinks and slowly moves towards the equator.
Warm-water currents travel out from the equator along the surface, flowing towards the poles to replace the sinking cold water.

Types of Ocean Currents Based on depth

The ocean currents may be classified based on their depth as surface currents anddeep water currents:

surface currents constitute about 10 per cent of all the water in the ocean, these waters are the upper 400 m of the ocean;
deep water currents make up the other 90 per cent of the ocean water. These waters move around the ocean basins due to variations in the density and gravity.

Deep waters sink into the deep ocean basins at high latitudes, where the temperatures are cold enough to cause the density to increase.

Based on temperature

Ocean currents are classified based on temperature: as cold currents and warm currents:

Cold currents bring cold water into warm water areas [from high latitudes to low latitudes]. These currents are usually found on the west coast of the continents(currents flow in clockwise direction in northern hemisphere and in anti-clockwise direction in southern hemisphere) in the low and middle latitudes (true in both hemispheres) and on the east coast in the higher latitudes in the Northern Hemisphere;
Warm currents bring warm water into cold water areas[low to high latitudes] and are usually observed on the east coast of continents in the low and middle latitudes (true in both hemispheres). In the northern hemisphere they are found on the west coasts of continents in high latitudes. Primary Forces Responsible For Ocean Currents Explain the factors responsible for the origin of ocean currents. How do they influence regional climates, fishing and navigation? [Mains 2015] Influence of insolation
Heating by solar energy causes the water to expand. That is why, near the equator the ocean water is about 8 cm higher in level than in the middle latitudes.
This causes a very slight gradient and water tends to flow down the slope. The flow is normally from east to west.
Influence of wind (atmospheric circulation)
Wind blowing on the surface of the ocean pushes the water to move. Friction between the wind and the water surface affects the movement of the water body in its course.
Winds are responsible for both magnitude and direction [Coriolis force also affects direction] of the ocean currents. Example: Monsoon winds are responsible for the seasonal reversal of ocean currents in the Indian ocean.
The oceanic circulation pattern roughly corresponds to the earth’s atmospheric circulation pattern.
The air circulation over the oceans in the middle latitudes is mainly anticyclonic [Sub-tropical High Pressure Belt] (more pronounced in the southern hemisphere than in the northern hemisphere due to differences in the extent of landmass). The oceanic circulation pattern also corresponds with the same.
At higher latitudes, where the wind flow is mostly cyclonic [Sub-polar Low Pressure Belt], the oceanic circulation follows this pattern.
In regions of pronounced monsoonal flow [Northern Indian Ocean], the monsoon winds influence the current movements which change directions according to seasons.
Influence of gravity
Gravity tends to pull the water down to pile and create gradient variation.
Influence of Coriolis force
The Coriolis force intervenes and causes the water to move to the right in the northern hemisphere and to the left in the southern hemisphere.
These large accumulations of water and the flow around them are called Gyres.These produce large circular currents in all the ocean basins. One such circular current is the Sargasso Sea.
Secondary Forces Responsible For Ocean Currents
Temperature difference and salinity difference are the secondary forces.
Differences in water density affect vertical mobility of ocean currents (vertical currents).
Water with high salinity is denser than water with low salinity and in the same way cold water is denser than warm water.
Denser water tends to sink, while relatively lighter water tends to rise.
Cold-water ocean currents occur when the cold water at the poles sinks and slowly moves towards the equator.
Warm-water currents travel out from the equator along the surface, flowing towards the poles to replace the sinking cold water.
Types of Ocean Currents Based on depth
The ocean currents may be classified based on their depth as surface currents anddeep water currents:
surface currents constitute about 10 per cent of all the water in the ocean, these waters are the upper 400 m of the ocean;
deep water currents make up the other 90 per cent of the ocean water. These waters move around the ocean basins due to variations in the density and gravity.
Deep waters sink into the deep ocean basins at high latitudes, where the temperatures are cold enough to cause the density to increase.
Based on temperature
Ocean currents are classified based on temperature: as cold currents and warm currents:
Cold currents bring cold water into warm water areas [from high latitudes to low latitudes]. These currents are usually found on the west coast of the continents(currents flow in clockwise direction in northern hemisphere and in anti-clockwise direction in southern hemisphere) in the low and middle latitudes (true in both hemispheres) and on the east coast in the higher latitudes in the Northern Hemisphere;
Warm currents bring warm water into cold water areas[low to high latitudes] and are usually observed on the east coast of continents in the low and middle latitudes (true in both hemispheres). In the northern hemisphere they are found on the west coasts of continents in high latitudes. Primary Forces Responsible For Ocean Currents Explain the factors responsible for the origin of ocean currents. How do they influence regional climates, fishing and navigation? [Mains 2015] Influence of insolation
Heating by solar energy causes the water to expand. That is why, near the equator the ocean water is about 8 cm higher in level than in the middle latitudes.
This causes a very slight gradient and water tends to flow down the slope. The flow is normally from east to west.
Influence of wind (atmospheric circulation)
Wind blowing on the surface of the ocean pushes the water to move. Friction between the wind and the water surface affects the movement of the water body in its course.
Winds are responsible for both magnitude and direction [Coriolis force also affects direction] of the ocean currents. Example: Monsoon winds are responsible for the seasonal reversal of ocean currents in the Indian ocean.
The oceanic circulation pattern roughly corresponds to the earth’s atmospheric circulation pattern.
The air circulation over the oceans in the middle latitudes is mainly anticyclonic [Sub-tropical High Pressure Belt] (more pronounced in the southern hemisphere than in the northern hemisphere due to differences in the extent of landmass). The oceanic circulation pattern also corresponds with the same.
At higher latitudes, where the wind flow is mostly cyclonic [Sub-polar Low Pressure Belt], the oceanic circulation follows this pattern.
In regions of pronounced monsoonal flow [Northern Indian Ocean], the monsoon winds influence the current movements which change directions according to seasons.
Influence of gravity
Gravity tends to pull the water down to pile and create gradient variation.
Influence of Coriolis force
The Coriolis force intervenes and causes the water to move to the right in the northern hemisphere and to the left in the southern hemisphere.
These large accumulations of water and the flow around them are called Gyres.These produce large circular currents in all the ocean basins. One such circular current is the Sargasso Sea.
Secondary Forces Responsible For Ocean Currents
Temperature difference and salinity difference are the secondary forces.
Differences in water density affect vertical mobility of ocean currents (vertical currents).
Water with high salinity is denser than water with low salinity and in the same way cold water is denser than warm water.
Denser water tends to sink, while relatively lighter water tends to rise.
Cold-water ocean currents occur when the cold water at the poles sinks and slowly moves towards the equator.
Warm-water currents travel out from the equator along the surface, flowing towards the poles to replace the sinking cold water.
Types of Ocean Currents Based on depth
The ocean currents may be classified based on their depth as surface currents anddeep water currents:
surface currents constitute about 10 per cent of all the water in the ocean, these waters are the upper 400 m of the ocean;
deep water currents make up the other 90 per cent of the ocean water. These waters move around the ocean basins due to variations in the density and gravity.
Deep waters sink into the deep ocean basins at high latitudes, where the temperatures are cold enough to cause the density to increase.
Based on temperature
Ocean currents are classified based on temperature: as cold currents and warm currents:
Cold currents bring cold water into warm water areas [from high latitudes to low latitudes]. These currents are usually found on the west coast of the continents(currents flow in clockwise direction in northern hemisphere and in anti-clockwise direction in southern hemisphere) in the low and middle latitudes (true in both hemispheres) and on the east coast in the higher latitudes in the Northern Hemisphere;
Warm currents bring warm water into cold water areas[low to high latitudes] and are usually observed on the east coast of continents in the low and middle latitudes (true in both hemispheres). In the northern hemisphere they are found on the west coasts of continents in high latitudes.