Influence of Oceanic Currents :
1. Influence on Temperature. Warm currents raise and cold currents lower the temperature of the coastal regions along which they flow. Labrador coast remains ice-bound for about nine months in a year due to the cold Labrador current.
On the other hand, the temperature of the British Isles remains comparatively high due to the warm Gulf Stream (a warm current in the North Atlantic Ocean),
2. Influence on Rainfall. Winds blowing over warm currents pick up moisture which when condenses causes heavy rains. On the other hand, winds blowing over cold currents get cold and thus do not pick up moisture. Therefore, they do not cause rains. Western Europe receives heavy rainfall due to the warm Gulf Stream. On the other hand, the western coasts of South America, Africa and Australia are washed by the cold currents and therefore, do not get any rain. As a result, big deserts such as Atacama (South America), Sahara, Kalahari and Namib (Africa) and West Australia have 1, formed.
3. Influence on Marine Life. Where a warm and cold current meet together, thick fog is formed. Near Newfoundland the warm Gulf Stream and the cold Labrador current meet together and this results in the formation of very thick fog. As a result, fish gather here in large number and these areas have become the fishing grounds of the world.
4. Influence of Navigation. In pre-steamship days the influence of currents was very important. The ships used to drift with the help of currents. Ships from India used to sail towards Iran and Arabia with the north-east monsoon drift in winter and would return to India with the south-west monsoon drift in summer. In the modern times also, ships prefer to sail with the ocean current as it adds to their speed.
