Physcis Photo of the Week

Physics Photo of the Week

December 6, 2024

Wake in clouds from mountain peak - satellite photos composed by D. Collins

 

The satellite image above shows the northeastern US in mid-winter (February 2024).  The left half of the image shows the many snow-covered lakes in the Adirondacks of northern New York.  The middle section shows snow-covered mountain ridges of Vermont that run north and south.  The mid right-center section shows a interesting piece of New Hampshire and a small gap in the clouds running southeast of a special white spot.  The white spot is the snow-capped summit of Mt. Washington breaking through the clouds and illuminated by the rising Sun.


The zoomed-in image at right shows the effect.  Mt. Washington's summit, at 6288 ft. above sea level, is the highest mountain point in the northeastern US*.  The summit has penetrated the cloud layer that was blowing towards the southeast.  The downstream part of the clouds show a wake in the cloud layer - very similar to the wake in a river caused by a protruding rock.  Notice the waves in the clouds as the wind-stream oscillated in elevation.  The waves resulted from the elastic "bouncing" of the wind after the impulse of rising suddenly to pass over the mountain peak.  This is very similar to the downstream ripples in a stream or river passing over partially submerged rocks.  


The animation at left is composed of satellite images made at 1 hour intervals beginning at dawn (7:45 local time) on February 8, 2024. The satellite images and animations were made from the site:

https://weather.ndc.nasa.gov/GOES/ 



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*Mount Mitchell in North Carolina, at 6684 feet, is the highest point in Eastern North America, almost 400 feet higher than Mount Washington in New Hampshire

 

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Physics Photo of the Week is published periodically during the academic year on Fridays by Donald F. Collins, professor emeritus of Warren Wilson College. These photos feature interesting phenomena in the world around us.  Students, faculty, and others are invited to submit digital (or film) photographs for publication and explanation. Atmospheric phenomena are especially welcome. Please send any photos to dcollins@warren-wilson.edu.

All photos and discussions are copyright by Donald Collins or by the person credited for the photo and/or discussion.  These photos and discussions may be used for private individual use or educational use.  Any commercial use without written permission of the photoprovider is forbidden.

To join the mailing list, please request to Donald Collins at the e-mail address below.  You will receive no more than one message every two weeks, or when a very interesting physics/astronomy event is happening.

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