Types of Ocean currents

These currents can be divided into surface currents and deep water currents according to their depth.

(i) Surface current—Making up around 10% of the ocean’s total water, these waters are found in the top 400 metres.

(ii) Deep water current—This makes up the remaining 90% of ocean water. Variations in density and gravity cause these waters to travel around the ocean basins.

Ocean Currents Classification (on the basis of temperature):

1. Cold Current- It flows from areas of low temperature to areas of high temperature.
2. Warm Current- It flows from areas of high temperature to areas of low temperature.

• Ocean current is a continuous, focused movement of seawater caused by factors including the earth’s rotation, wind, temperature, salinity differences, air pressure, and differences in the density of the seawater, among others. The rotation of the globe has little impact on ocean currents.
• Water in the ocean can move both horizontally and vertically. Vertical shifts are referred to as upwellings or downwellings whereas horizontal movements are known as currents.
• Ocean currents resemble river flows. They show a consistent flow of water traveling in a specific path and direction. There are two different types of forces that affect ocean currents: (i) primary forces, which cause the water to start moving, and (ii) secondary forces, which cause the current to flow.
• Solar-generated heat, winds, gravity, and the Coriolis force are the main factors that affect currents. The water expands as a result of solar heating.
• Trade winds cause the ocean currents to flow in opposite directions, clockwise in the Northern Hemisphere and anticlockwise in the Southern.