Zonal and meridional flow

[2] These terms are often used in the atmospheric and earth sciences to describe global phenomena, such as "meridional wind", or "zonal average temperature".

In the context of physics, zonal flow connotes a tendency of flux to conform to a pattern parallel to the equator of a sphere.

In meteorological term regarding atmospheric circulation, zonal flow brings a temperature contrast along the Earth's longitude.

Extratropical cyclones in zonal flows tend to be weaker, moving faster and producing relatively little impact on local weather.

For vector fields (such as wind velocity), the zonal component (or x-coordinate) is denoted as u, while the meridional component (or y-coordinate) is denoted as v. In plasma physics, "zonal flow" means poloidal, which is the opposite from the meaning in planetary atmospheres and weather/climate studies.