The North Atlantic Drift is a broadening wind drift under the influence of the south-westerlies. It is also known as the North Atlantic Current which is, as a matter of fact, the continuation of the Gulf Stream after it leaves the Grand Banks.

It consists of several branches which are broader in width than the Gulf Stream. The characteristic features of this current is that its branches are separated by eddies and counter-currents.

It should be borne in mind that these currents vary during the entire year and move predominantly towards the east. The branching of the North Atlantic Current has been established by the German and Norwegian research vessels Altair and Armauer Hansen.

The branch currents of the North Atlantic Drift approach Europe, thereby losing their predominantly easterly direction owing to the influence of the continent.

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These branches not only send extensions towards the north (the Norwegion Current) and towards the south (the Portugal Current), but also enter the area of the continental shelf of the North Atlantic Ocean as in the Irish Sea, the English Channel and the North Sea.

The northward flowing branch passes through the Davis Strait between Baffin Land and Greenland, and another approaches the south coast of Iceland.

Another branch of the main drift continues along the Scandinavian coast as the Norwegian Current on into the Barents Sea and towards Spitzbergen.

The remaining branches turn south between Spain and the Azores, and flow southwards along the African coast as the cold Canaries Current. In this way the clockwise circulation of the North Atlantic is completed.

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The cooling of the southwards flowing Canaries Current is due to the up-welling of cold water off the coast of North Africa. This planetary circulation encloses the Sargasso Sea with the relatively still waters in it. In this sea the floating seaweeds are found in abundance.

It may be stated that the eastern branch of the North Atlantic Drift bathes the coasts of Spain and France and after crossing the Mid-Atlantic Ridge at 45°N latitude bends towards the right of its path. This is, perhaps, due to the influence of the bottom relief of the ocean and the Coriolis force.

According to Helland-Hansen and Nansen, the absence of distinct ocean currents in this region is peculiar in its own way. However, a diffuse transport of water towards the south does take place.

Some of this water flows into the Mediterranean Sea as a surface current through the Strait of Gibraltar. It is to be noted that there is a return subsurface flow out of this sea across the sill in the strait.

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This water is highly saline and spreads at intermediate depths. In fact, this water with a very high degree of salinity affects the water masses of the greater part of the North and South Atlantic Ocean.

The upper water masses maintain their flow towards the south, and ultimately join the North Equatorial Current.

As a result of the presence of the North Atlantic Drift in the ocean, positive temperature anomalies are recorded in major part of the region towards the west and the central part. But in the southeastern part there are certain areas with negative temperature anomalies.

Remember that water which is transported from the tropical to the higher latitudes is naturally warm, whereas water being transported from the Polar Regions to lower latitudes is relatively cold.

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Another characteristic feature of the system of currents is that the Gulf Stream transports large volumes of water off Chesapeake Bay with temperatures above 16°C, whereas the North Atlantic Drift carries only small amounts of water of the same temperature to the north of Azores.