Ocean currents are body of water mass with a slightly different thermophysical characteristic viz temperature, density and salinity from the surrounding water body. They move in a well-defined path like a river in the ocean and is influenced by the direction of wind and the coastal features.

Ocean currents have far reaching impacts on the coastal economy. Ocean currents affects coastal economy in many ways such as

Agriculture

• Ocean currents influence the climate of the coastal regions and, in many cases, well beyond the coast. Such influence, characterized mostly by temperature, precipitation and cloud cover, and consequently the length of the growing season, determines the type of agriculture and hence many other economic activities of the region.

Fishing industry

• The most effective, reliable, and productive areas for industrial fishing are located where the cold ocean currents (carrying oxygen) meet warm ocean currents rich in nutrients.
• In East Asia meeting of the warm Kuroshio and the cold Oyashio current provides ideal conditions for rich fishing grounds in Japan. However, navigation becomes difficult due to thick fog.

Energy from Ocean Currents

• The massive oceanic surface currents are untapped reservoirs of renewable energy, probably the largest on the planet. Even if only a small portion of ocean currents energy can be harnessed, the potential of “hydro” energy that is embedded in ocean currents is remarkable.
• A key concern is how the turbines could affect local marine ecosystems. The turbines would be located at depths of about 100 meters, in areas of fast-moving water. In many zones, the main animals to worry about would be large marine mammals, like whales and dolphins

El Niño and La Niña

• The terms of El Niño and La Niña are frequently used when the weather patterns of the Pacific Ocean are discussed. Both of these contrasting patterns appear irregularly every few years, but they bring the likely weather patterns of sometimes extreme rains or the absence of rains, respectively.
• The consequences of El Niño may be substantial on weather of all countries with Eastern Pacific seashores, and consequently on the economy (fishing and agriculture) and health (epidemic diseases).

Ports

• The warm current is also responsible natural maintenance of ports .
  Eg – warm gulf current play an effective role in melting the ice in north European nation ports during winter.

Climate

• Ocean currents act as global conveyor belts which transfer heat from one part of the earth to another. They regulate the coastal climate thereby indirectly regulating the vegetation, fauna and the lifestyles of the people.

Others

• Ocean currents affect the shipping industry, commercial and recreational fishing, and recreational navigation for boats. 
• They play a role in the distribution of pollution, such as oil spills. Oil and fuel tends to remain on the surface of the ocean, so knowing the current helps determine where such pollution might travel.

Ocean currents do indeed play a significant role ushering in the necessary weather changes, which at the same time, dictate the ways in which physiography, livelihoods and coastal economy of the world are impacted.