Ocean surface currents

Ocean surface currents are the movement of water at the surface of the ocean. These currents are driven by a variety of factors, including wind, tides, and the Earth’s rotation. They can be divided into two main categories: wind-driven currents and thermohaline currents. The adjective thermohaline derives from thermo- referring to temperature and -haline referring to salt content.

This article was produced by Global Solo Challenge

Wind-driven currents are caused by the friction between the wind and the surface of the water, which creates a horizontal movement of water. This movement is driven by the prevailing winds and the Coriolis effect, the latter is a phenomenon caused by the rotation of the Earth and is responsible for the rotation of the wind patterns and ocean currents, as well as the direction of storms and low-pressure systems. Wind currents can be further divided into two types: Ekman currents and geostrophic currents. Ekman currents are caused by the friction between the wind and the surface of the water, while geostrophic currents are caused by the balance of the horizontal pressure gradient, which is the change in atmospheric pressure over a horizontal distance and is responsible for the formation of winds, and the Coriolis effect.

On the other hand, thermohaline currents are driven by the density of the water, which is affected by temperature and salinity. These currents are caused by the sinking of cold, dense water and the rise of warm, less dense water. The most notable example of thermohaline current is the ocean conveyor belt, also known as the thermohaline circulation, which is responsible for the global ocean circulation and has a significant impact on the Earth’s climate.

Ocean surface currents play an important role in the global climate and weather patterns, as well as in marine ecosystem, shipping and ocean-based industries.

However, ocean surface currents are not to be confused with tidal currents. Tidal currents are the horizontal movement of water caused by the rise and fall of tides. They are caused by the gravitational pull of the moon and the sun on the Earth’s oceans, and can be observed in the form of ebbing and flowing of water in coastal areas. Tidal currents can be quite strong in certain locations, and are an important consideration for navigation and marine activities such as fishing and boating but do not affect navigation at all once skippers in the Global Solo Challenge will be offshore.

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