There is an excellent example of cobblestone cirrus over France this
morning. This cloud arises due to contamintion of the moist upper layers,
probably by Saharan dust in this case. The dust particles provide a vast
store of condensation nuclei, allowing thick ice cloud to form where it
would otherwise be absent or tenuous. This in turn alters the radiation
balance in the upper troposphere, causing the lapse rate to steepen towards
the dry adiabatic rate, and allowing convection to become widespread in the
upper layers of the cloud, and producing the cobblestone appearance.

http://www.woksat.info/etcacd21m/thu...ketcacd21m.jpg

http://www.woksat.info/etcacd21m/thu...ketcacd21m.jpg



--
Bernard Burton
Weather data and satellite images at:
www.woksat.info/wwp.html

Correction to image address

There is an excellent example of cobblestone cirrus over France this
morning. This cloud arises due to contamintion of the moist upper layers,
probably by Saharan dust in this case. The dust particles provide a vast
store of condensation nuclei, allowing thick ice cloud to form where it
would otherwise be absent or tenuous. This in turn alters the radiation
balance in the upper troposphere, causing the lapse rate to steepen towards
the dry adiabatic rate, and allowing convection to become widespread in the
upper layers of the cloud, and producing the cobblestone appearance.

http://www.woksat.info/etcacd21m/ful...sg-0900-uk.JPG

http://www.woksat.info/etcacd21m/ful...sg-0600-uk.JPG



--
Bernard Burton
Weather data and satellite images at:
www.woksat.info/wwp.html

On Tuesday, April 21, 2020 at 10:43:11 AM UTC+1, Bernard Burton wrote:
Correction to image address

There is an excellent example of cobblestone cirrus over France this
morning. This cloud arises due to contamintion of the moist upper layers,
probably by Saharan dust in this case. The dust particles provide a vast
store of condensation nuclei, allowing thick ice cloud to form where it
would otherwise be absent or tenuous. This in turn alters the radiation
balance in the upper troposphere, causing the lapse rate to steepen towards
the dry adiabatic rate, and allowing convection to become widespread in the
upper layers of the cloud, and producing the cobblestone appearance.

http://www.woksat.info/etcacd21m/ful...sg-0900-uk.JPG

http://www.woksat.info/etcacd21m/ful...sg-0600-uk.JPG



--
Bernard Burton
Weather data and satellite images at:
www.woksat.info/wwp.html

Interesting Bernard,
Thanks.
I have n't heard that term used before.

Len

wrote:

On Tuesday, April 21, 2020 at 10:43:11 AM UTC+1, Bernard Burton wrote:
Correction to image address

There is an excellent example of cobblestone cirrus over France this
morning. This cloud arises due to contamintion of the moist upper
layers, probably by Saharan dust in this case. The dust particles
provide a vast store of condensation nuclei, allowing thick ice
cloud to form where it would otherwise be absent or tenuous. This
in turn alters the radiation balance in the upper troposphere,
causing the lapse rate to steepen towards the dry adiabatic rate,
and allowing convection to become widespread in the upper layers of
the cloud, and producing the cobblestone appearance.

http://www.woksat.info/etcacd21m/ful...sg-0900-uk.JPG

http://www.woksat.info/etcacd21m/ful...sg-0600-uk.JPG



--
Bernard Burton
Weather data and satellite images at:
www.woksat.info/wwp.html

Interesting Bernard,
Thanks.
I have n't heard that term used before.

Len

I haven't heard it either but the satellite imagery was very striking
this morning.

--
Norman Lynagh
Tideswell, Derbyshire
303m a.s.l.
https://peakdistrictweather.org
twitter: @TideswellWeathr

On 21/04/2020 16:27, wrote:
On Tuesday, April 21, 2020 at 10:43:11 AM UTC+1, Bernard Burton wrote:
Correction to image address

There is an excellent example of cobblestone cirrus over France this
morning. This cloud arises due to contamintion of the moist upper layers,
probably by Saharan dust in this case. The dust particles provide a vast
store of condensation nuclei, allowing thick ice cloud to form where it
would otherwise be absent or tenuous. This in turn alters the radiation
balance in the upper troposphere, causing the lapse rate to steepen towards
the dry adiabatic rate, and allowing convection to become widespread in the
upper layers of the cloud, and producing the cobblestone appearance.

http://www.woksat.info/etcacd21m/ful...sg-0900-uk.JPG

http://www.woksat.info/etcacd21m/ful...sg-0600-uk.JPG



--
Bernard Burton
Weather data and satellite images at:
www.woksat.info/wwp.html

Interesting Bernard,
Thanks.
I have n't heard that term used before.


New one for me too. I wonder what it looks like from below.


--
Graham P Davis, Bracknell, Berks. Web-site: http://www.scarlet-jade.com/
“Understanding is a three-edged sword. Your side, my side, and the
truth.� [Ambassador Kosh]
Posted via Mozilla Thunderbird on openSUSE Tumbleweed.

On Tuesday, 21 April 2020 19:49:55 UTC+1, Graham P Davis wrote:
On Tuesday, April 21, 2020 at 10:43:11 AM UTC+1, Bernard Burton wrote:

Bernard,

I too had not heard that term before, but I have been curious for some time whether there were names for the different types of cloud seen from space. Is there a catalog of clou shapes as viewed from space?

Alastair.