I suppose if I truly want to take the weekend off, I’ll have to ditch my smartphone. These photos from the Facebook page of the Panhandle Helicopter Service in Panama City Beach, Florida, have been making the rounds today, erroneously labeled by ABC, MSNBC, and other news outlets as a “tsunami cloud”. Hence my humorous headline. Here’s the pictures in a clickable gallery:
The explanation for this phenomenon is very simple.
Nearly saturated (at almost the dew point) air from a sea breeze is being lifted (Orographic lifting) as it meets the coast and the buildings. The slight cooling from the lifting cools the air to the dew point and clouds form.
A similar phenomenon can be seen on some ocean islands.
I wondered about the use of the term “orographic” to refer to this sea-level phenomenon, since (I thought) the root “oro” means “mountain”. I looked it up and found that oro is also linked to the word “rise”, so… guess that’s how it applies. Orogenesis is “mountain-making, especially by folding of the earth’s crust.”
I wondered also if this wasn’t the term for the cloud-making process on Kilimanjaro. Googling “orographic uplift kilimanjaro”, ALL the top seven featured articles (the first page on my screen) appear to acknowledge this “land use” phenomenon on Kili, using variations like “orographic clouds”, “orographic uplift”, “orographic lift”, “orographic precipitation”. Even a NOVA “interactive” (make your own cloud) cites this science without reference to AGW.
A small triumph.
One of those articles, btw, explains the process in terms very familiar to readers here ; – )
http://powerpointparadise.com/blog/2010/08/kilimanjaro%E2%80%99s-snow-it%E2%80%99s-about-land-use-change-tree-cutting/
Yes we often see this here, Mannanan’s cloak it is called locally.
A couple of photos here:
http://dailyphotoisleofman.blogspot.com/2009/01/manannans-cloak-monochrome-oddshots.html
Kindest Regards
eyesonu-
no problem I enjoy the discussion
to answer your “elementary” question, if it is done suddenly, which would be appropriate for a shock wave or in the wind over the hotel or the shedding vortices on a plane wing (basically most types of fluid flow situations) the event will occur ISOTHERMALLY (temperature will remain roughly constant) and the increase in pressure will result in condensation to occur. however, if it is done gradually over time, as is the case with weather patterns, the process is largely ISENTROPIC (no change in entropy) and the increase in pressure will also result in an increase in temperature so the relative humidity will actually go down.
however, as I said- at a constant temperature, an increase in pressure will increase the relative humidity and COULD result in condensation if the change is sufficiently large
one other thing- fog and rolling mists and marine layers are a different phenomenon than what is seen on the hotels. they are indeed temperature driven scenarios that occur from the cooling of large masses of high humidity air. the dead giveaway are the flowlines that are evident on the hotels or the other examples- that indicates it is a flow induced (and therefore pressure induced) phenom
@ur momisugly JPS
I started todays ‘trek’ by accessing the publication by Ascher Shapiro, Fundamentals of Compressible Flow Mechanics, (it is available online) and that led me to a publication by Leroy Henderson, General Laws for Propagation of Shockwaves Through Matter, (also available online). That leads to yet deeper analysis as I have yet to find the inclination to dive into. I’ve got to quit asking myself questions!
The SR-71 reading detailing the compression wave formed at the cone of the engine intake was also very interesting.
Thanks again for the exchange, or in my case the gain, of knowledge. Once again, it’s that vast wealth of useless knowledge thing. 😉
If we hit a tipping point, all that water could make the sky catch on fire.
Just sayin..
Up at our place we routinely experience upslope fog.
@ur momisugly JPS or anyone who may have gotten curious with regards to the OT discussion of a condensation cloud formed at the point of the creation of a sonic boom
It seems that I was searching for an answer and it may have been “the tipping point” all along.
Pressure waves, compression waves, shock waves, expansion waves, sub-sonic waves, supersonic waves, Prandtl-Glauert singularity, fold catastrophe, cusp catastrophe, cusp bifurcations, fold bifurcation, pitchfork bifurcation, hysteresis loops, and more terms than you can imagine. I have finally arrived at the tipping point literally.
Don’t go there unless you really really want some brain candy. I have got to get this hand injury healed before I drive myself to the tipping point!
I wonder why Maldives ex-president Mohamed Nasheed’s supporters and international do not accept that Nasheed is mentally sick and he is the lier of the century. He should not be back in power. He could be the most currupted leader of the century too. He has robbed the assets of Maldives given to his supporters and has put the country in debt. International community should very carefully read the new constitution of Maldives. Nasheed’s cult do not understand the implications of their actions to the country. They are fighting back to come to the power to hide the illeagal actions. When Nasheed’s resignation was so sudden politians did not have time to remove or hide any evidence. Nasheed’s party, MDP members do not accept the constitution and laws they have endosed. Most of the MP’s supporting MDP is very currupt irresponsible people.
This is the same effect that causes the famous ‘cap cloud’ over Mt. Rainier, southeast of Seattle.