geostrophic current
Quick Summary
Geostrophic currents are a type of fluid flow that occurs when the Coriolis force, caused by Earth's rotation, balances the pressure-gradient force. This balance results in the fluid moving parallel to lines of equal pressure, known as isobars.1
On a non-rotating planet, fluid would move directly from high to low pressure. However, Earth's rotation deflects this movement. In the Northern Hemisphere, the Coriolis force deflects the flow to the right, while in the Southern Hemisphere, it deflects to the left. This balance is described by the geostrophic balance equation.2
Geostrophic currents are significant in large-scale oceanic and atmospheric movements, often representing the actual current within about 10 percent accuracy, especially where isobars are not sharply curved. The term "ageostrophic" describes motion that is not caused or affected by the Coriolis force.13
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ocean currentGeostrophic currents…of current is called a geostrophic current. The simple equation given above provides the basis for an indirect method of computing ocean currents. The relief of the sea surface also defines the streamlines (paths) of the geostrophic current at the surface relative to the deep reference level. The hills represent…
Read More…of current is called a geostrophic current. The simple equation given above provides the basis for an indirect method of computing ocean currents. The relief of the sea surface also defines the streamlines (paths) of the geostrophic current at the surface relative to the deep reference level. The hills represent…
Read More- climateThe Gulf Stream
…rise to a dynamically induced geostrophic current, which occurs throughout the upper layer of warm water. The strength of this geostrophic current is determined by the horizontal pressure gradient through the slope in sea level. The slope in sea level across the Gulf Stream has been measured by satellite radar…
Read More…rise to a dynamically induced geostrophic current, which occurs throughout the upper layer of warm water. The strength of this geostrophic current is determined by the horizontal pressure gradient through the slope in sea level. The slope in sea level across the Gulf Stream has been measured by satellite radar…
Read More