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Thread: The BA Cloud!
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Old May 24, 2012, 3:15 pm
  #28  
BotB
 
Join Date: Nov 2010
Location: Bristol, UK
Programs: HH D, Rad Plat
Posts: 5,352
Originally Posted by henkybaby

Originally Posted by steve_w
Okay, these two photos show the difference between a text book Cumulus cloud (from henkybaby ^) with very sharp, well defined edges to the cloud (see how the cauliflower bumps have very good contrast to the air and you feel you 'know' exactly where the cloud starts and ends) to the very different Cumulus fractus sub species in steve_w's picture...the edges of the clouds in the foreground are much less precise around the edges and seem to gradually 'fade' into the air (also the colour tends to be a gradient from the brilliant white through a number of shades of grey to almost transparent)...this 'blurry' edging tends to be what is called either Stratus cloud or a fractus sub species of a cloud...depending on how it was formed...Here (still talking about steve_w's clouds in the foreground) it is Cumulus fractus as the type of cloud in the air is a convective cloud formed from the heating of the atmosphere and hot air rising to cool off and then subsiding after it becomes quite cool and sinks to warm up again...The fractus clouds here are different to the background well defined Cumulus or TCU because there is less heating here in the foreground as the Sun is behind cloud or is not heating this air as much as the air in the background and these CU fractus are effectively only small isolated pockets where there is still some convection and a small amount of remaining super saturation that forms the fractions of cloud at that height...effectively trying to balance out the temperature and moisture in the air parcels here...in the background the much more well developed TCU are still being heated from the Sun on top as well as the rising warm air from below and probably some sea breezes from the land to water exchange as well...These TCU will develop even further and quicker in such warm, moist locations when the Sun is setting or just rising as the atmosphere is effectively experiencing a very abrupt and strong 'flipping' of the hot / cold air...during the day the lower surfaces are warmer and try to rise and the upper heights are colder and try to sink...but when the Sun is strong or it is Summer (in the Northern Hemisphere at least) then when the Sun goes down or is just rising the air at the upper heights is actually heated more than the lower regions (in morning) or the air at height is cooling far quicker than it was previously and therefore sinks quicker causing the convection to seem to be on 'boil' setting for about 20 - 30 minutes until some equilibrium is reached and things balance out again...for this reason we get more showers of rain and cloud development around mid morning and just after the Sun is setting in the evening! It is also why some clouds that previously only gave rain showers in the afternoon or early morning then suddenly give lightning and thunder as they get that little bit extra 'kick' from the atmosphere to become a full CB cloud and have the energy to produce the extra 'effects'...

Sorry, get a bit excited about the power and forces at action from mother nature in these pics and tend to go off on one...hope it is still of interest and makes sense? Let me know if something is not clear and I'll try to do better next time...promise!

Excellent Pictures everyone, thanks for contributing...keep them coming please! ^^^

Originally Posted by HIDDY
I thought they were supposed to be BA related?
It is desired that the pictures are indeed taken from BA aircraft (hence the blue engine cowls showing in Prospero's pics ^ ) or a UK location or at least have some tie to BA or UK city, etc...I am certain the MOD's will forgive the odd excursion into foreign parts or transgression...but to keep this thread here we do need to keep this BA relevant please where possible!^
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