Lee waves. These are internal gravity #waves revealed by the #clouds. They are generated as slightly denser air parcels are pushed up (where the air is less dense) as the wind blows over  a obstacle like a #mountain. Then, as the air parcel is heavier than its surroundings, it sinks and overshoots. That is how the wave #oscillation is started.

I shot this while in the #Pyrenees last week, a #timelapse condensing 5 minutes into 15 seconds.

#science #physics #atmosphere
https://fediscience.org/system/media_attachments/files/113/158/855/750/116/594/original/18f682f74adac70e.mp4
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