Kelvin-Helmholtz Wave Clouds Observed During Eclipse

November 21, 2017

Eclipse Kelvin Waves (1)

Photographers: Katelyn Nichols; Joy Hughes 
Summary Authors: Katelyn Nichols; Jim Foster

November 2017 Viewer's ChoiceThe photo above shows Kelvin-Helmholtz wave clouds captured on August 21, 2017, as we were observing the total solar eclipse just south of Salem, Oregon. A characteristic of these wave clouds is their breaking wave appearance; a result of air in the lower layers of the wave moving somewhat slower than the layers above it (wind shear). The more marked the shear, the more obvious the Kelvin-Helmholtz instability feature. Temperature inversions and or rather abrupt changes in temperature with altitude can play a role in their formation.