Wave Clouds Off the Eastern Coast of Brazil22.9S 43.2W
Wave clouds leave rippled patterns in the skies off the east coast of Brazil. Near the shore, the cities of São Paulo (left) and Rio de Janeiro (right) appear as grey areas amidst the green of coastal mountains and forests.
A wave cloud is a cloud form created by atmospheric standing waves. When there is enough moisture in the atmosphere, clouds form at the crests of these waves, but evaporate in the descending parts due to adiabatic heating. This creates the characteristic repeating cloud/clear bands.