Airglow Above the Tibetan Plateau

August 16, 2014

Atmospheric Gravity Waves

Photographer: Jeff Dai
Summary AuthorJeff Dai

This fisheye view of the nighttime sky shows an incredible display of banded airglow that filled the entire sky over the Tibetan Plateau in late April of 2014. This glow is predominantly created by the excitation of atoms by ultraviolet light from the Sun. But what's the reason for the ripple-like structure?  It's due to atmospheric gravity waves, the oscillations of air parcels by the lifting force of buoyancy and the restoring force of gravity. These unusual gravity waves likely resulted from violent thunderstorms over Bangladesh (upper right), some 180 mi (300 km) away. Air currents over the Himalayas acted to enhance the waves. Photo taken on April 27, 2014.