APOD: Mammatus Clouds Over Saskatchewan (2012 Oct 23)

Comments and questions about the APOD on the main view screen.
User avatar
APOD Robot
Otto Posterman
Posts: 4533
Joined: Fri Dec 04, 2009 3:27 am

APOD: Mammatus Clouds Over Saskatchewan (2012 Oct 23)

Post by APOD Robot » Tue Oct 23, 2012 4:06 am

Image Mammatus Clouds Over Saskatchewan

Explanation: Normal cloud bottoms are flat. This is because moist warm air that rises and cools will condense into water droplets at a specific temperature, which usually corresponds to a very specific height. As water droplets grow, an opaque cloud forms. Under some conditions, however, cloud pockets can develop that contain large droplets of water or ice that fall into clear air as they evaporate. Such pockets may occur in turbulent air near a thunderstorm. Resulting mammatus clouds can appear especially dramatic if sunlit from the side. These mammatus clouds were photographed over Regina, Saskatchewan, Canada during the past summer.

<< Previous APOD This Day in APOD Next APOD >>
[/b]

User avatar
Beyond
500 Gigaderps
Posts: 6889
Joined: Tue Aug 04, 2009 11:09 am
Location: BEYONDER LAND

Re: APOD: Mammatus Clouds Over Saskatchewan (2012 Oct 23)

Post by Beyond » Tue Oct 23, 2012 4:32 am

Mamma-mia, datsa soma spec-a-tactular Mammatus :!: :!:
To find the Truth, you must go Beyond.

Boomer12k
:---[===] *
Posts: 2691
Joined: Sun Apr 22, 2007 12:07 am

Re: APOD: Mammatus Clouds Over Saskatchewan (2012 Oct 23)

Post by Boomer12k » Tue Oct 23, 2012 5:34 am

Thought it was bubble wrap for a moment...

:---[===]*

User avatar
Ann
4725 Å
Posts: 11737
Joined: Sat May 29, 2010 5:33 am

Re: APOD: Mammatus Clouds Over Saskatchewan (2012 Oct 23)

Post by Ann » Tue Oct 23, 2012 5:36 am

Ah, mammatus clouds! :D They are named after "breasts", which they resemble. They make me want to post a picture of a woman nursing her baby, but I don't think that would be allowed! :wink:

Then again, these clouds are full of water - and soon after the picture was taken, the Earth was probably nursing these clouds, drinking water from them! How extremely lucky we are to have water falling from the sky, usually in suitable amounts.

Of course, if we hadn't had a precipation cycle with involving liquid water, we wouldn't have been the same kind of beings that we are now. Alternatively, we wouldn't have existed at all. Take your pick.

But these swelling mammatus clouds are a beautiful reminder of the fertility of planet Earth.

Ann
Color Commentator

User avatar
Moonlady
Selenian
Posts: 665
Joined: Fri Apr 13, 2012 9:06 pm

Re: APOD: Mammatus Clouds Over Saskatchewan (2012 Oct 23)

Post by Moonlady » Tue Oct 23, 2012 6:13 am

At first sight, I thought clouds are going to fall down...not as single drops, more like fogg coming down...

This is a fascinating pic, makes me wonder how gases are doing on other planets, like Jupiter, what kind of clouds, gases they have and how it would look
watching Jupiter's sky from the inside...

starsurfer
Stellar Cartographer
Posts: 4625
Joined: Thu Mar 15, 2012 7:25 pm

Re: APOD: Mammatus Clouds Over Saskatchewan (2012 Oct 23)

Post by starsurfer » Tue Oct 23, 2012 6:47 am

Ann wrote:swelling mammatus clouds

Ann
OMG! Is that even allowed here?! :D

User avatar
neufer
Vacationer at Tralfamadore
Posts: 18759
Joined: Mon Jan 21, 2008 1:57 pm
Location: Alexandria, Virginia

Re: APOD: Mammatus Clouds Over Saskatchewan (2012 Oct 23)

Post by neufer » Tue Oct 23, 2012 12:06 pm

starsurfer wrote:
Ann wrote:
swelling mammatus clouds
OMG! Is that even allowed here?! :D
All part of our Regina Monologues.
Art Neuendorffer

User avatar
orin stepanek
Plutopian
Posts: 7107
Joined: Wed Jul 27, 2005 3:41 pm
Location: Nebraska

Re: APOD: Mammatus Clouds Over Saskatchewan (2012 Oct 23)

Post by orin stepanek » Tue Oct 23, 2012 12:43 pm

i'd be lost without my pockets! :D :wink:
Orin

Smile today; tomorrow's another day!

User avatar
geckzilla
Ocular Digitator
Posts: 9158
Joined: Wed Sep 12, 2007 12:42 pm
Location: Modesto, CA

Re: APOD: Mammatus Clouds Over Saskatchewan (2012 Oct 23)

Post by geckzilla » Tue Oct 23, 2012 1:19 pm

Oh, come on, there's nothing wrong with showing breasts or especially not an infant breastfeeding, as long as it's on topic, which in that case it would be odd to randomly talk about breasts. Of course, you wouldn't want to look at the above two links if you were at work. It might alert the boss to the fact that you are messing around on Asterisk!
Just call me "geck" because "zilla" is like a last name.

Strangerbarry

Re: APOD: Mammatus Clouds Over Saskatchewan (2012 Oct 23)

Post by Strangerbarry » Tue Oct 23, 2012 1:51 pm

Re: "Normal cloud bottoms are flat. This is because moist warm air that rises and cools will condense into water droplets at a specific temperature, which usually corresponds to a very specific height. "

Wouldn't this mean the TOPS should be flat ?

florid_snow
Ensign
Posts: 42
Joined: Thu Nov 04, 2010 4:54 am

Re: APOD: Mammatus Clouds Over Saskatchewan (2012 Oct 23)

Post by florid_snow » Tue Oct 23, 2012 3:28 pm

Strangerbarry wrote:Re: "Normal cloud bottoms are flat. This is because moist warm air that rises and cools will condense into water droplets at a specific temperature, which usually corresponds to a very specific height. "

Wouldn't this mean the TOPS should be flat ?
As different parcels of clear air rise, they all cool at the same rate and reach the condensation temperature at the same level, and the cloud's base appears flat. Then, as different parcels of cloudy air rise (towards the top), their vertical velocity will change based on how much they mix with the environment. If a cloud is still warm enough to be rising, it will not have a flat top, but a buoyant bubbly looking top.

The parcels of cloudy air will eventually reach a level where they are no longer buoyant; you'd think they'd all stop there and be flat. But some may still have positive vertical velocity by that level and overshoot the top, bouncing around a bit before spreading out flat. You are probably familiar with flat top clouds, anvil clouds. That's cloudy air that has reached it's non-buoyancy level at a very specific temperature, with corresponds to a very specific height because the atmosphere is so spread out horizontally. Explaining the distribution of cloud top heights is the fundamental question a convection parameterization answers for a climate model.

To explain mammatus clouds (which almost always form on the underside of anvils) you must explain their bubbly buoyant appearance. The text under the APOD uses the old explanation, that bigger cloud particles settle in the lobes and are sinking. Another explanation is that as the anvil spreads over warm dry land it is heated by radiation from the ground, and develops a convective bubbly appearance. The mammatus lobes are just what's left behind as other sections of the anvil are gently heated and begin to rise up. This would also explain why mammatus rarely form when it is very humid at levels below the anvil (water vapor absorbs the ground's radiation, reducing what the anvil is exposed to). Since this theory explains more but is slightly simpler, it is more compelling.

Signed,
A grad student reading too many papers about this

http://journals.ametsoc.org/doi/abs/10. ... lCode=atsc

User avatar
emc
Equine Locutionist
Posts: 1249
Joined: Tue Jul 17, 2007 12:15 pm
AKA: Bear
Location: Canton, GA, USA

Re: APOD: Mammatus Clouds Over Saskatchewan (2012 Oct 23)

Post by emc » Tue Oct 23, 2012 3:32 pm

At first, I saw an interesting cloud formation of “bubbles”. But after reading the caption and everyone’s comments… all I see are a lot of breasts… there are two close together that are of particular interest… gee…thanks… I guess. I am supposed to work some today… now my mind is clouded with mammatus.

jm3

Re: APOD: Mammatus Clouds Over Saskatchewan (2012 Oct 23)

Post by jm3 » Tue Oct 23, 2012 3:41 pm

Great shot Craig, nice work!

rustie58
Asternaut
Posts: 1
Joined: Tue Oct 23, 2012 4:23 pm

Re: APOD: Mammatus Clouds Over Saskatchewan (2012 Oct 23)

Post by rustie58 » Tue Oct 23, 2012 4:42 pm

The day after these clouds every facebook page from someone in Regina had pictures of these amazing clouds that covered the city in the evening, it was a beautiful surreal sight.

Never mind the breast jokes....Regina was also noted by Mick jagger as the city that rhymes with fun

User avatar
BMAONE23
Commentator Model 1.23
Posts: 4076
Joined: Wed Feb 23, 2005 6:55 pm
Location: California

Re: APOD: Mammatus Clouds Over Saskatchewan (2012 Oct 23)

Post by BMAONE23 » Tue Oct 23, 2012 4:54 pm

The first time I saw these i thought of Massive Posteriors floating in the sky. A heavenly BA if you will

ta152h0
Schooled
Posts: 1398
Joined: Mon Aug 29, 2005 12:46 am
Location: Auburn, Washington, USA

Re: APOD: Mammatus Clouds Over Saskatchewan (2012 Oct 23)

Post by ta152h0 » Tue Oct 23, 2012 5:04 pm

just imagine what our ancestors thought a few millenia ago upon seeing this and deciding which god was mad that day ?
Wolf Kotenberg

TNT
Science Officer
Posts: 289
Joined: Mon Oct 03, 2011 1:57 am
Location: Heart of America

Re: APOD: Mammatus Clouds Over Saskatchewan (2012 Oct 23)

Post by TNT » Tue Oct 23, 2012 5:52 pm

Another way mammatus cloud formation can occur is by "reverse-direction convection." This happens when convection in these clouds is so strong that it not only develops an overshooting top, but warm air travels to the underside of the anvil creating pockets of warm air, thus producing this odd formation.
The following statement is true.
The above statement is false.

User avatar
geckzilla
Ocular Digitator
Posts: 9158
Joined: Wed Sep 12, 2007 12:42 pm
Location: Modesto, CA

Re: APOD: Mammatus Clouds Over Saskatchewan (2012 Oct 23)

Post by geckzilla » Tue Oct 23, 2012 5:57 pm

ta152h0 wrote:just imagine what our ancestors thought a few millenia ago upon seeing this and deciding which god was mad that day ?
And maybe, just maybe, one of them sat and pondered what really caused the clouds to do that.
Just call me "geck" because "zilla" is like a last name.

User avatar
Beyond
500 Gigaderps
Posts: 6889
Joined: Tue Aug 04, 2009 11:09 am
Location: BEYONDER LAND

Re: APOD: Mammatus Clouds Over Saskatchewan (2012 Oct 23)

Post by Beyond » Tue Oct 23, 2012 7:57 pm

geckzilla wrote:
ta152h0 wrote:just imagine what our ancestors thought a few millenia ago upon seeing this and deciding which god was mad that day ?
And maybe, just maybe, one of them sat and pondered what really caused the clouds to do that.
And just what would someone have gotten from 'pondering', way back then?
To find the Truth, you must go Beyond.

ta152h0
Schooled
Posts: 1398
Joined: Mon Aug 29, 2005 12:46 am
Location: Auburn, Washington, USA

Re: APOD: Mammatus Clouds Over Saskatchewan (2012 Oct 23)

Post by ta152h0 » Tue Oct 23, 2012 9:22 pm

geckzilla wrote:
ta152h0 wrote:
just imagine what our ancestors thought a few millenia ago upon seeing this and deciding which god was mad that day ?

And maybe, just maybe, one of them sat and pondered what really caused the clouds to do that.
And just what would someone have gotten from 'pondering', way back then?

invention of the wheel, so the ancient ponderer could follow them....I need an ice cold one
SW
Wolf Kotenberg

stonecherub

Re: APOD: Mammatus Clouds Over Saskatchewan (2012 Oct 23)

Post by stonecherub » Wed Oct 24, 2012 12:12 am

OK, I get the formation of the bubbles but why are they in such sharply defined lines?

FLPhotoCatcher
Science Officer
Posts: 196
Joined: Wed Jul 18, 2012 6:51 am

Re: APOD: Mammatus Clouds Over Saskatchewan (2012 Oct 23)

Post by FLPhotoCatcher » Wed Oct 24, 2012 7:42 am

florid_snow, I read the abstract in the link, and do not agree, though I think the standard explanation for the formation of mammatus clouds may not be complete either. To me, it's clear that mammatus clouds are not formed just from the heating of the underside of anvil clouds. If that were the case, then most anvil clouds over warm dry land would grow them.

I have seen them in Florida several times, and Florida is usually quite humid, and seemed to be at the times. Most every time, they formed under the anvil of a severe storm. The main differences between the anvil of a severe storm and the anvil of an average storm, is its thickness, and the height of it. The thicker an anvil cloud is, the more precip (in the form of snow) there is, and the more precip there is, the more and stronger the downdrafts are. These downdrafts may indeed have to be above air that is drier than average. When the downdrafts hit the drier air, the snow sublimates and contributes moisture to the dry air, thus making the air around the downdraft lobe more buoyant, and causing it to rise around and between the lobes. Heat radiation from the ground may add to the buoyancy of the outsides of the lobes. In a house fire, you will get flames below the ceiling that look similar when "flashover" occurs (google flashover to see some pictures). These flames that look like mammatus clouds are caused by cooler and denser flammable vapors (smoke) falling down from the ceiling and then igniting on contact with oxygen and existing flame.