ICSE Class 7 Answered

The effects of ocean currents are:

• Affect Temperatures: Currents influence the climatic conditions of the regions in which they flow. The warm Equatorial currents raise the temperature of the region in which they flow. Similarly, the cold currents lower the temperature of the places where they flow. For example, British Isles would have been extremely cold without the warm North Atlantic Drift. The hot climate of Peru is cooled by the cold Peru Current.
• Affect Rainfall: The winds blowing over warm currents pick up and carry moisture and bring rainfall like the North Atlantic Drift bring rainfall in some areas located along the western coasts of Europe. On the contrary, cold currents do not bring rainfall and make the region cooler and drier. The Kalahari Desert hardly experiences rainfall due to the cold Benguela current.
• Fog: The meeting of the warm and the cool currents results in the formation of fog.
• Violent Storms: At times the meeting line of a warm and a cold current may result into a violent storm. The hurricanes which occur off the coast of U.S.A. follow the line where the Gulf Stream merges with the Labrador Current.
• The mixing of warm and cold currents results in the deposition of planktons. Therefore, at such places, fishes can be found in abundance.
• Currents help ships to sail if they follow the directions of the currents.
• Many warm currents keep the ports of Europe ice free even during the winters. This helps in trade and commerce.
• The ships face danger due to the fogs caused by the meeting of the warm currents with the cold currents. This has resulted in the wreckage of many ships in the past as they are not able to view icebergs due to poor visibility.