Internal waves at 30.0S, 134.0E (near Australia) from shuttle mission STS048 at altitude of 307 nauts

Internal waves in wake of Galapagos Islands from shuttle mission STS053 at altitude of 201 nauts

More internal waves in wake of Galapagos Islands from shuttle mission STS059 at altitude of 115 nauts

More internal waves in wake of Galapagos Islands from shuttle mission STS059 at altitude of 115 nauts

Internal waves spotted by a satellite (details unknown)

Internal waves in lee of an island spotted by AVHRR satellite on Feb. 1, 1996. (this image courtesy of Brett N. Lesh, Scripps Institute of Oceanography)

Internal waves appear to be generated by a dynamic instability. Photographed by me in north-west Indiana, December 28, 1994.

Internal waves generated by tidal flow through the Straight of Gibraltar. Photo taken during shuttle mission 41G, 12:21:48, Oct 10, 1984.

More internal waves in the Straight of Gibraltar. Photo taken during shuttle mission 41G, 12:04:04 GMT, Oct 11, 1984. Note, the surface elevation varies by only about 20cm, but the amplitude of the waves well below the surface can be many tens of meters!

More internal waves in the Straight of Gibraltar. Photo taken during shuttle mission 41G, 12:04:06 GMT, Oct 11, 1984.

Internal waves generated by tidal flow over the shelf near Hainan Island. Each wavepacket is produced during high tides every 12 hours. Photo taken during shuttle mission STS-7, Jun 23, 1983.

Vortices over Atlantic Ocean at 31.0N, 18.2W from shuttle mission STS047 at altitude of 166 nauts

Dipole vortices near Baja Peninsula from shuttle mission STS069 at altitude of 199 nauts

Vortex near Tampico (22.0N, 97.0W) from shuttle mission STS062 at altitude of 161 nauts

Vortices of different scales (details unknown)