New vs. dissipating clouds

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TheDrafter
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New vs. dissipating clouds

Post by TheDrafter » Thu Aug 09, 2018 10:07 am

Hi,

Is it possibble to tell the difference between new and dissipating cumulus clouds in Condor?

// Mikkel

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OXO
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Re: New vs. dissipating clouds

Post by OXO » Thu Aug 09, 2018 11:10 am

Yes.

But its a subtle difference, as in real life. :D
Chris Wedgwood,
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TheDrafter
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Re: New vs. dissipating clouds

Post by TheDrafter » Thu Aug 09, 2018 1:23 pm

Okay great :)
I'll have to practise telling the difference then.

Spirals
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Re: New vs. dissipating clouds

Post by Spirals » Thu Aug 09, 2018 4:41 pm

Hi The Drafter

An hour or two cross country in the Grunau in less than ideal conditions will definitely help.

One; you have plenty and plenty of time to observe the clouds as you approach them as it takes ages and you will definitely see them dying in front of you and

Two; you can't afford to get it wrong too often otherwise you are just watching from a field.

I'm pretty sure I can tell the difference between forming and dissipating but I have no idea how to explain it so it is quite close to real life.

I think there is more 'form' to clouds that are forming and less firmness (a fuzziness almost) with the clouds that are dying.

Best of luck
Steve
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janjansen
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Re: New vs. dissipating clouds

Post by janjansen » Thu Aug 09, 2018 11:14 pm

The difference is subtle for sure. I think the easiest way to see it is the darkness of the base. I made a timelapse "training video" :


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Bre901
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Re: New vs. dissipating clouds

Post by Bre901 » Fri Aug 10, 2018 8:50 am

Nice video, thanks !
One interesting thing to notice (especially in the first part of the video): one can see very well the difference between ridge thermals and flatland ones : ridge thermal clouds (green dots) do not drift with wind whereas the flatland ones do :D :D
take a look at 0:19 close to the right hand border of the screen
CN: MPT — CondorUTill webpage: https://condorutill.fr/

TheDrafter
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Re: New vs. dissipating clouds

Post by TheDrafter » Fri Aug 10, 2018 11:19 am

Spirals wrote:
Thu Aug 09, 2018 4:41 pm
Hi The Drafter

An hour or two cross country in the Grunau in less than ideal conditions will definitely help.

One; you have plenty and plenty of time to observe the clouds as you approach them as it takes ages and you will definitely see them dying in front of you and

Two; you can't afford to get it wrong too often otherwise you are just watching from a field.

I'm pretty sure I can tell the difference between forming and dissipating but I have no idea how to explain it so it is quite close to real life.

I think there is more 'form' to clouds that are forming and less firmness (a fuzziness almost) with the clouds that are dying.

Best of luck
Steve

Thanks for the tips, Steve! Sounds like a really good exersice :D
janjansen wrote:
Thu Aug 09, 2018 11:14 pm
The difference is subtle for sure. I think the easiest way to see it is the darkness of the base. I made a timelapse "training video" :


Wow great video! It seems the new clouds are much more defined actually. Thank you Jan!

Crakob
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Re: New vs. dissipating clouds

Post by Crakob » Sun Aug 12, 2018 12:14 pm

Interesting indeed

And i always thought, the source of a thermal, cornfield, city or whatsoever, would be stationary an the hose or bubble of uprising air would drift with the wind.

This looks quite different from what I learned ??? ( the source of the thermal moves too]

Christian
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Re: New vs. dissipating clouds

Post by OXO » Sun Aug 12, 2018 1:20 pm

Crakob wrote:
Sun Aug 12, 2018 12:14 pm
Interesting indeed

And i always thought, the source of a thermal, cornfield, city or whatsoever, would be stationary an the hose or bubble of uprising air would drift with the wind.

This looks quite different from what I learned ??? ( the source of the thermal moves too]

Christian
You can confirm our model by downloading igc files from a flatland gliding competition and see that the gliders at different heights are still stacked vertically ==>> therefore the whole thermal moves with the wind.

Mountain thermals are different..
Chris Wedgwood,
Condor Team

TheDrafter
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Re: New vs. dissipating clouds

Post by TheDrafter » Tue Aug 14, 2018 9:08 am

Crakob wrote:
Sun Aug 12, 2018 12:14 pm
You can confirm our model by downloading igc files from a flatland gliding competition and see that the gliders at different heights are still stacked vertically ==>> therefore the whole thermal moves with the wind.

Mountain thermals are different..

That is a very interesting fact, as most places thermals are explained as almost static, slanting with the wind.

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Re: New vs. dissipating clouds

Post by janjansen » Tue Aug 14, 2018 11:40 am

Sometimes you can see a thermal forming on the ground, because of dust or leaves forming a small "tornado". And just like a real tornado, you will notice they move with the wind. This is also my experience with RC gliders. They may not move as fast as the wind, and thermals could also be slanted if for no other reason then the wind gradient.

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timbaeyens
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Re: New vs. dissipating clouds

Post by timbaeyens » Tue Aug 14, 2018 3:17 pm

The wind gradient is there mainly due to surface friction, so Jan is correct.
TT

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Re: New vs. dissipating clouds

Post by NaderFam » Thu Jul 01, 2021 7:31 pm

It seems that Condor flatland thermals are always columns.

There is of course another type of thermal as described in many sources, that are basically bubbles that rise alone and not continuously like a plume. You can fly under or above a rising bubble and miss it. The bottom and top have the least lift, while the fat vertical center of the bubble has the most.

There are still discussions about which type is the real one, and that will probably continue until we have devices that can capture thermals optically by measuring the refraction index up and down the plume or the bubble, sort of like RL thermal helpers.

Some pilots have reported bubbles within columns, and columns. Although I haven't seen any report of multiple bubbles from the same source, but I am quite new here and not anywhere near an expert in atmospheric knowledge.
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