Looking for billow clouds

First I wondered where that solitary cloud was going. Then I noticed a longer ‘tail’ of similar clouds following it, looking vaguely like billow clouds. Are they billow clouds? Billow clouds are the product of a Kelvin-Helmholtz instability. If two fluids are flowing in parallel layers at different velocities, and have different densities, then the … Read more

Billow clouds, shocked streams & shedding eddies

I flew from Bangalore to Delhi on Tuesday. The flight was early in the day, at 6, and so I had the wonderful opportunity to watch a sunrise from above a sea of clouds. One very beautiful sight was the presence of uniquely shaped ones, styled like the waves in Hokusai’s The Great Wave off Kanagawa. I recalled having … Read more