Why are surface currents at the surface of the ocean?
Surface Ocean Currents. The water at the ocean surface is moved primarily by winds that blow in certain patterns because of the Earth's spin and the Coriolis Effect. Gyres flow clockwise in Northern Hemisphere oceans and counterclockwise in Southern Hemisphere oceans because of the Coriolis Effect.
Surface wind-driven currents generate upwelling currents in conjunction with landforms, creating deepwater currents. Currents may also be generated by density differences in water masses caused by temperature and salinity variations. Both move masses of water inland when they reach shallow water and coastlines.
- Four Factors That Create Ocean Currents
- Wind. Wind is the single biggest factor in the creation of surface currents.
- Water Density. Another major factor in the creation of currents is water density, caused by the amount of salt in a body of water, and its temperature.
- Ocean Bottom Topography.
- Coriolis Effect.
- Deep ocean currents (also known as Thermohaline Circulation) are caused by: The density of sea water varies globally due to differences in temperature and salinity. Surface water is heated by the sun, and warm water is less dense than cold water.
- B. Surface currents are controlled by three factors: global winds, the Coriolis effect, and continental deflections. surface create surface currents in the ocean. Different winds cause currents to flow in different directions. objects from a straight path due to the Earth's rotation.
In these areas, the balance between gravity and Earth's spin causes geostrophic currents to flow. Deep ocean currents are caused by differences in water temperature and salinity (density).
- Warm ocean currents flow away from the equatorial region on the western side of ocean basins. The Gulf Stream in the North Atlantic and the Kuroshio Current in the North Pacific are examples of warm currents. Of all the warm currents, the Gulf Stream has been studied most extensively.
- This deflection is called the Coriolis effect. Click the image for a larger view. Coastal currents are affected by local winds. Surface ocean currents, which occur on the open ocean, are driven by a complex global wind system.
- For the considerably longer periods– decades to millennia – which are relevant for climate change, the significantly larger heat capacity of the deep ocean is important. Ocean currents and mixing by winds and waves can transport and redistribute heat to deeper ocean layers.
Updated: 17th October 2019