Waves, Planetary

PLANETARY-SCALE WAVES HAVE their origin relating to the Earths shape and rotation; the waves are so large that some of them wrap around the whole Earth and can be observed in the atmosphere through the meandering of the jet stream. A long wave or planetary wave is a weather system that circles the world, with one to three waves forming a looping path around the Earth at any given time and displacing air north and south. Planetary waves have ridges (the high points) and troughs (the low points). Warmer upper air is associated with an increasing number of waves or stronger waves.

Planetary waves form in the lowest part of the atmosphere, called the troposphere, and propagate upward, transferring energy into the stratosphere and heating polar ...