What type of gyres are balanced between gravity and the Coriolis Effect?

Geostrophic gyres are established through the balance between the gravitational forces acting on water and the Coriolis Effect, which is caused by the rotation of the Earth. This balance results in a situation where the flow of water moves perpendicular to the pressure gradient created by differences in water height.

In the context of ocean currents, gravity causes water to flow from high to low areas, while the Coriolis Effect acts to deflect moving water to the right in the Northern Hemisphere and to the left in the Southern Hemisphere. When these forces reach equilibrium, the flow of water in gyres becomes circular, maintaining a consistent pattern around large ocean basins.

Other types of gyres, such as coastal or equatorial gyres, do not represent this balance in the same way, as they can be influenced by additional factors such as landmasses, wind patterns, and variations in ocean temperature and salinity. Transverse gyres specifically refer to the orientation of currents rather than the force balance that characterizes geostrophic gyres. Thus, the concept of geostrophic gyres is paramount in understanding how ocean currents are organized and maintained.