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View Full Version : MODIS: Internal Waves in the Andaman Sea


ELEN
29-05-04, 05:01
May 29, 2004

The Andaman Sea, like all large bodies of water, is composed of layers of water with differing densities. The topmost layer is the least dense, with each successively deeper layer being denser. Internal waves move along underwater at the boundary between layers of different densities.

Internal waves are usually caused by the lower layer being forced against a shallow obstacle (such as a ridge) by tidal action. The ridge causes a disturbance, which creates a wave in the water layer, similar to the way that the wind can cause waves on the water’s surface. However, unlike normal surface waves, internal waves can stretch tens of kilometers in length and move throughout the ocean for several hours.

Internal waves alter sea surface currents, changing the overall "sea surface roughness". Where these currents converge, the sea surface is more turbulent, and therefore brighter. Where the currents diverge, the surface is smoother and darker, creating zones called "slicks". In this true-color Terra MODIS image from April 22, 2004, the slicks created by internal waves appear as dark bands in the center of the image.

http://modis.gsfc.nasa.gov/gallery/images/image05292004_md.jpg

COPYRIGHT, NASA 2004

crazyguy100
29-05-04, 05:06
Thanks Elen for the info. As always, interesting things!! (that nasty school http://www.tombraiderforums.com/images/smilies/violent.gif ) Can I send you a PM? I'd post here, but it's just for you, and I don't want others to read it http://www.tombraiderforums.com/images/smilies/redface.gif (hehe)

ELEN
29-05-04, 05:25
Sure Crazy. My PM's are enabled http://www.tombraiderforums.com/images/smilies/smile.gif

crazyguy100
29-05-04, 05:44
Ok Elen. I'll send it later, it's too late over here (almost 2:00), so I'll send it in 12 or 13 hours. So, goodnight!

http://www.tombraiderforums.com/images/smilies/wave.gif (posted just to let you know)

Dorothy
17-06-04, 10:00
FANTASTISCH!