Between the North Equatorial and South Equatorial Currents, there is an easterly moving Equatorial Counter Current in the Doldrums, the belt of calm, which compensates to a certain extent the piling-up of the water on the western side of the ocean.

These counter currents belong to the most conspicuous parts of the oceanic circulation. They form narrow bands, which can almost always be traced over the entire width of the individual oceans in a zonal direction.

They flow from west to east with an average velocity of 50cm/sec. In extreme cases the velocities of 150 cm/sec may be attained. Such velocities are among the highest in the open ocean. In July, this counter-current is more strongly developed than in January.

In fact, the Equatorial Counter -Current is a down-slope current between the two up-sloping currents i.e. the North Equatorial Current and the South Equatorial Current.

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The counter-current is a very shallow current which is confined to the surface layer above the discontinuity. This counter-current, on the eastern side of the Atlantic merges into the Guinea Current which flows towards the east. This current flows with a high velocity along the African west coast.

As stated above, during summer months this counter current is more strongly developed. In winter, on the contrary, it is in the form of a feeble current with no full development.

In the northern winter the counter current begins east of 24°W; whereas in the northern summer it starts east of 50°W and can be seen over the entire width of the Atlantic Ocean.

Throughout the year, this counter-current is divided into two parts-the western part and the eastern part. In the western part, it is weak and its width is limited.

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This part of the current develops during the winter season only, whereas the eastern part can be seen all the year round. During summer the two parts of the current join and produce a very strong current.

This strong and powerful counter-current develops to the west of 50° West longitude in the vicinity of the north coast of South America. The latitudinal extent of the width of this current is from 3°N latitude to 10°N latitude.

When this current is fully developed, there is a zone of convergence in its central part. Water from the north and south starts flowing towards this convergence zone.