# Amazing Kelvin-Helmholtz waves over Birmingham **URL:** \ **Category:** Miscellaneous and Personal Stuff I Must Share\ **Created:** [December 16, 2011, 8:12pm UTC](https://boards.straightdope.com/t/amazing-kelvin-helmholtz-waves-over-birmingham/606444 "2011-12-16T20:12:36Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![Ogre](https://avatars.discourse-cdn.com/v4/letter/o/ecb155/32.png) [@Ogre](https://boards.straightdope.com/u/Ogre)\ **Post date:** [December 16, 2011, 8:12pm UTC](https://boards.straightdope.com/t/amazing-kelvin-helmholtz-waves-over-birmingham/606444/1 "2011-12-16T20:12:36Z")
[Check this out](http://farm8.staticflickr.com/7164/6522284917_cdb2212da4_b.jpg) I pulled over on the interstate to take this photo. What you’re looking at is a phenomenon called a Kelvin-Helmholtz instability. The ridgeline directly ahead had been cloaked in heavy fog all morning, and as a cold front came through, it sent strong, laminar winds above and along the ridge. This resulted in lower pressure just above the fog layer. The fog was lifted off the mountain and “rolled forward” in the distinctive way you see by encountering the laminar flow aloft. This was really, really cool to see. At its peak, there were 7 well-formed waves lined up down the ridge. This is a phenomenon you see fairly commonly in cloud layers, but I’ve never, ever seen it on the ground. ---
**Author:** ![Sunspace](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/sunspace/32/1250_2.png) [@Sunspace](https://boards.straightdope.com/u/Sunspace)\ **Post date:** [December 16, 2011, 8:16pm UTC](https://boards.straightdope.com/t/amazing-kelvin-helmholtz-waves-over-birmingham/606444/2 "2011-12-16T20:16:52Z")
Wow! I’ve never seen anything like that. ---
**Author:** ![Greg\_Charles](https://avatars.discourse-cdn.com/v4/letter/g/839c29/32.png) [@Greg\_Charles](https://boards.straightdope.com/u/Greg_Charles)\ **Post date:** [December 16, 2011, 8:22pm UTC](https://boards.straightdope.com/t/amazing-kelvin-helmholtz-waves-over-birmingham/606444/3 "2011-12-16T20:22:33Z")
Thanks for posting that! It really is amazing. ---
**Author:** ![cjepson](https://avatars.discourse-cdn.com/v4/letter/c/a9adbd/32.png) [@cjepson](https://boards.straightdope.com/u/cjepson)\ **Post date:** [December 16, 2011, 8:47pm UTC](https://boards.straightdope.com/t/amazing-kelvin-helmholtz-waves-over-birmingham/606444/4 "2011-12-16T20:47:31Z")
You should submit that photo to the [Atmospheric Optics](http://www.atoptics.co.uk/) site. ---
**Author:** ![Ogre](https://avatars.discourse-cdn.com/v4/letter/o/ecb155/32.png) [@Ogre](https://boards.straightdope.com/u/Ogre)\ **Post date:** [December 16, 2011, 8:57pm UTC](https://boards.straightdope.com/t/amazing-kelvin-helmholtz-waves-over-birmingham/606444/5 "2011-12-16T20:57:17Z")
> [@cjepson](#): > > You should submit that photo to the [Atmospheric Optics](http://www.atoptics.co.uk/) site. Done! Thanks very much for linking that site. It’s fantastic! ---
**Author:** ![Kolga](https://avatars.discourse-cdn.com/v4/letter/k/e56c9b/32.png) [@Kolga](https://boards.straightdope.com/u/Kolga)\ **Post date:** [December 16, 2011, 8:58pm UTC](https://boards.straightdope.com/t/amazing-kelvin-helmholtz-waves-over-birmingham/606444/6 "2011-12-16T20:58:12Z")
That photo and the science lesson are both very cool. Thanks for sharing! ---
**Author:** ![Ogre](https://avatars.discourse-cdn.com/v4/letter/o/ecb155/32.png) [@Ogre](https://boards.straightdope.com/u/Ogre)\ **Post date:** [December 16, 2011, 9:46pm UTC](https://boards.straightdope.com/t/amazing-kelvin-helmholtz-waves-over-birmingham/606444/7 "2011-12-16T21:46:07Z")
> [@cjepson](#): > > You should submit that photo to the [Atmospheric Optics](http://www.atoptics.co.uk/) site. Just heard back from Les Cowley (wow that was fast!) He doesn’t post non-optical effects on his web page, but he directed me to the [Cloud Appreciation Society](http://cloudappreciationsociety.org/), to which I have submitted the photo. ---
**Author:** ![Snowboarder\_Bo](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/snowboarder_bo/32/229_2.png) [@Snowboarder\_Bo](https://boards.straightdope.com/u/Snowboarder_Bo)\ **Post date:** [December 16, 2011, 9:58pm UTC](https://boards.straightdope.com/t/amazing-kelvin-helmholtz-waves-over-birmingham/606444/8 "2011-12-16T21:58:16Z")
That is an awesome photo (and a darn good science summary of what caused it too). ---
**Author:** ![Lsura](https://avatars.discourse-cdn.com/v4/letter/l/7993a0/32.png) [@Lsura](https://boards.straightdope.com/u/Lsura)\ **Post date:** [December 16, 2011, 9:59pm UTC](https://boards.straightdope.com/t/amazing-kelvin-helmholtz-waves-over-birmingham/606444/9 "2011-12-16T21:59:56Z")
That’s a cool picture! Thanks for sharing. 🙂 ---
**Author:** ![Bloodless\_Turnip](https://avatars.discourse-cdn.com/v4/letter/b/82dd89/32.png) [@Bloodless\_Turnip](https://boards.straightdope.com/u/Bloodless_Turnip)\ **Post date:** [December 16, 2011, 10:27pm UTC](https://boards.straightdope.com/t/amazing-kelvin-helmholtz-waves-over-birmingham/606444/10 "2011-12-16T22:27:00Z")
Amazing stuff, thanks for posting! ---
**Author:** ![Ogre](https://avatars.discourse-cdn.com/v4/letter/o/ecb155/32.png) [@Ogre](https://boards.straightdope.com/u/Ogre)\ **Post date:** [December 16, 2011, 10:47pm UTC](https://boards.straightdope.com/t/amazing-kelvin-helmholtz-waves-over-birmingham/606444/11 "2011-12-16T22:47:27Z")
Thanks all! Associated goodness: I have posted commentary on a local weather blog, and have attracted the unwanted attentions of a chemtrail conspiracy theorist who seems to be convinced that the K-H waves are evidence of the government experimenting on the good citizens of our country. :rolleyes:, an infinity of :rolleyes: ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [December 16, 2011, 11:17pm UTC](https://boards.straightdope.com/t/amazing-kelvin-helmholtz-waves-over-birmingham/606444/12 "2011-12-16T23:17:14Z")
> [@Ogre](#): > > Thanks all! > > Associated goodness: I have posted commentary on a local weather blog, and have attracted the unwanted attentions of a chemtrail conspiracy theorist who seems to be convinced that the K-H waves are evidence of the government experimenting on the good citizens of our country. > > :rolleyes:, an infinity of :rolleyes: What a maroon! Our government can’t do that. It obviously is the result of alien technology. ---
**Author:** ![Ogre](https://avatars.discourse-cdn.com/v4/letter/o/ecb155/32.png) [@Ogre](https://boards.straightdope.com/u/Ogre)\ **Post date:** [December 17, 2011, 6:35am UTC](https://boards.straightdope.com/t/amazing-kelvin-helmholtz-waves-over-birmingham/606444/13 "2011-12-17T06:35:27Z")
Somebody shoot me. The chemtrail “activists” are all over that weather blog now (either that, or one person with multiple socks) talking about the TRUTH of government geo-engineering, and how they have thousands of activists, and how it can’t be a natural phenomenon, because it looks all weird and shit. Stupid, haunted, superstitious cretins. These would be the same idiots accusing their neighbors of being witches in the old days. ---
**Author:** ![Phedre\_no\_Delaunay](https://avatars.discourse-cdn.com/v4/letter/p/839c29/32.png) [@Phedre\_no\_Delaunay](https://boards.straightdope.com/u/Phedre_no_Delaunay)\ **Post date:** [December 19, 2011, 4:46am UTC](https://boards.straightdope.com/t/amazing-kelvin-helmholtz-waves-over-birmingham/606444/14 "2011-12-19T04:46:33Z")
What the heck have they done putting all that facebook crap on there anyway? That has always been my go-to weather place and now it’s almost unreadable. :mad: ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [December 19, 2011, 4:53am UTC](https://boards.straightdope.com/t/amazing-kelvin-helmholtz-waves-over-birmingham/606444/15 "2011-12-19T04:53:31Z")
> [@Ogre](#): > > Somebody shoot me. The chemtrail “activists” are all over that weather blog now (either that, or one person with multiple socks) talking about the TRUTH of government geo-engineering, and how they have thousands of activists, and how it can’t be a natural phenomenon, because it looks all weird and shit. > > Stupid, haunted, superstitious cretins. These would be the same idiots accusing their neighbors of being witches in the old days. Well no. They might be the descendants of the idiots who accused their neighbors of witchcraft in the old days. But they could be the same idiots accusing their neighbors of being witches now-a-days though. ---
**Author:** ![Ale](https://avatars.discourse-cdn.com/v4/letter/a/f19dbf/32.png) [@Ale](https://boards.straightdope.com/u/Ale)\ **Post date:** [December 19, 2011, 1:50pm UTC](https://boards.straightdope.com/t/amazing-kelvin-helmholtz-waves-over-birmingham/606444/16 "2011-12-19T13:50:39Z")
Cool photos, however I’m deeply disturbed that when reading the thread title I actually knew what a Kelvin-Helmholtz wave was. I need to get out more often. 😛 ---
**Author:** ![Angua](https://avatars.discourse-cdn.com/v4/letter/a/8baadc/32.png) [@Angua](https://boards.straightdope.com/u/Angua)\ **Post date:** [December 19, 2011, 2:38pm UTC](https://boards.straightdope.com/t/amazing-kelvin-helmholtz-waves-over-birmingham/606444/17 "2011-12-19T14:38:24Z")
> [@Ale](#): > > Cool photos, however I’m deeply disturbed that when reading the thread title I actually knew what a Kelvin-Helmholtz wave was. > > I need to get out more often. 😛 Nah, I read the thread title, said “cool!” as well, and then started wondering if I could work out stuff about the instability from the picture. And then realized that not only had turbulent flows taken over my work life, they were just taking over my life. 😉 ---
**Author:** ![Ogre](https://avatars.discourse-cdn.com/v4/letter/o/ecb155/32.png) [@Ogre](https://boards.straightdope.com/u/Ogre)\ **Post date:** [December 19, 2011, 4:31pm UTC](https://boards.straightdope.com/t/amazing-kelvin-helmholtz-waves-over-birmingham/606444/18 "2011-12-19T16:31:45Z")
Yeah well, this is how much of a nature/weather/science geek I am: I’m pretty sure I was the first person in the city to identify it as a K-H instability. We were driving on the interstate, and I saw the fog (really a very low cloud layer) start to destabilize in places. As we were passing into the downtown area, I saw the beginnings of telltale “peaks” in the fog spaced at regular intervals. Right then, before any distinctive wave forms were discernible, I shouted “Kelvin-Helmholtz!” I can’t really imagine that anybody else on the planet beat me to the punch on that one. 🙂 I broke off in the middle of a conversation with my wife about Christopher Hitchens, and she momentarily thought I’d lost my mind. Within just a couple of minutes, the waves were fully formed, and we stopped on the side of the road to take photos. ---
**Author:** ![Hbns](https://avatars.discourse-cdn.com/v4/letter/h/8edcca/32.png) [@Hbns](https://boards.straightdope.com/u/Hbns)\ **Post date:** [December 19, 2011, 4:51pm UTC](https://boards.straightdope.com/t/amazing-kelvin-helmholtz-waves-over-birmingham/606444/19 "2011-12-19T16:51:25Z")
> [@TriPolar](#): > > What a maroon! Our government can’t do that. It obviously is the result of alien technology. Or James May’s Man Lab trying to make snow again. ---
**Author:** ![WordMan](https://avatars.discourse-cdn.com/v4/letter/w/e8c25b/32.png) [@WordMan](https://boards.straightdope.com/u/WordMan)\ **Post date:** [December 19, 2011, 6:38pm UTC](https://boards.straightdope.com/t/amazing-kelvin-helmholtz-waves-over-birmingham/606444/20 "2011-12-19T18:38:30Z")
> [@Snowboarder\_Bo](#): > > That is an awesome photo (and a darn good science summary of what caused it too). +1. [QUOTE=Ogre] Right then, before any distinctive wave forms were discernible, I shouted “Kelvin-Helmholtz!” I can’t really imagine that anybody else on the planet beat me to the punch on that one. [/QUOTE] Only on the 'dope…meteorological wackiness and you play some mean guitar, too. [Next page](https://boards.straightdope.com/t/amazing-kelvin-helmholtz-waves-over-birmingham/606444.md?page=2)