A-68A turning again.


geojohnt@...
 

All,

Todays Metop image via EUMETCast shows the iceberg rotating again.
And, is the pointed bit breaking away?

Not sure about the line across the centre of the iceberg - cloud edge shadow?

Regards,
John.


Ferdinand Valk
 

There is indeed some calving at the pointed tip. Bits can be seen floating nearby. The line you see across the centre is caused by cloud. Most of the fault lines visible in the sar imagery run lengthwise through the slab; there is one major fault though at the root of the pointing finger that may well be the first to rupture.

 

Ferdinand

 

From: MSG-1@groups.io On Behalf Of geojohnt via groups.io
Sent: Tuesday, 22 December, 2020 12:55
To: msg-1@groups.io; geo-subscribers@groups.io
Subject: [MSG-1] A-68A turning again.

 

All,

 

Todays Metop image via EUMETCast shows the iceberg rotating again.

And, is the pointed bit breaking away?

 

Not sure about the line across the centre of the iceberg - cloud edge shadow?

 

Regards,

John.


geojohnt@...
 

Hello Ferdinand,

Thanks for the amazing image.
Such incredible detail and as you say bits floating nearby having broken off.

I agree about the cloud edge shadow line but enlarging todays Metop image to 300% although blurred appears to show(?) a black crack/line/area - which again could be shadow - at the base area of the finger, but it seems to correspond to the fault line in your image?

Regards,
John.

++++++++++++++++++++++++++

-----Original Message-----
From: Ferdinand Valk <fvalk@...>
To: MSG-1@groups.io
Sent: Tue, 22 Dec 2020 14:25
Subject: Re: [MSG-1] A-68A turning again.

There is indeed some calving at the pointed tip. Bits can be seen floating nearby. The line you see across the centre is caused by cloud. Most of the fault lines visible in the sar imagery run lengthwise through the slab; there is one major fault though at the root of the pointing finger that may well be the first to rupture.
 
Ferdinand
 
From: MSG-1@groups.io On Behalf Of geojohnt via groups.io
Sent: Tuesday, 22 December, 2020 12:55
To: msg-1@groups.io; geo-subscribers@groups.io
Subject: [MSG-1] A-68A turning again.
 
All,
 
Todays Metop image via EUMETCast shows the iceberg rotating again.
And, is the pointed bit breaking away?
 
Not sure about the line across the centre of the iceberg - cloud edge shadow?
 
Regards,
John.


Ferdinand Valk
 

Yes John, that is correct. The fault line I refer to in the sar image is the same as the black line you see in your Metop and also in the attached Sentinel 3B image of today. The black in the colour image is the surface melt filling up the crack: this is the principal reason to suspect this line to give way first.

 

From: MSG-1@groups.io On Behalf Of geojohnt via groups.io
Sent: Tuesday, 22 December, 2020 15:42
To: MSG-1@groups.io
Subject: Re: [MSG-1] A-68A turning again.

 

Hello Ferdinand,

 

Thanks for the amazing image.

Such incredible detail and as you say bits floating nearby having broken off.

 

I agree about the cloud edge shadow line but enlarging todays Metop image to 300% although blurred appears to show(?) a black crack/line/area - which again could be shadow - at the base area of the finger, but it seems to correspond to the fault line in your image?

 

Regards,

John.


++++++++++++++++++++++++++

-----Original Message-----
From: Ferdinand Valk <fvalk@...>
To: MSG-1@groups.io
Sent: Tue, 22 Dec 2020 14:25
Subject: Re: [MSG-1] A-68A turning again.

There is indeed some calving at the pointed tip. Bits can be seen floating nearby. The line you see across the centre is caused by cloud. Most of the fault lines visible in the sar imagery run lengthwise through the slab; there is one major fault though at the root of the pointing finger that may well be the first to rupture.

 

Ferdinand

 

From: MSG-1@groups.io On Behalf Of geojohnt via groups.io
Sent: Tuesday, 22 December, 2020 12:55
To: msg-1@groups.io; geo-subscribers@groups.io
Subject: [MSG-1] A-68A turning again.

 

All,

 

Todays Metop image via EUMETCast shows the iceberg rotating again.

And, is the pointed bit breaking away?

 

Not sure about the line across the centre of the iceberg - cloud edge shadow?

 

Regards,

John.


Ernst Lobsiger
 

Ferdinand,
Users of my Sentinel-3A/B scripts,

an exeptional Sentinel-3B image from A68a today. It seems the iceberg will leave the sgeorgia300 area soon. The easiest way to follow will be an update of the personal areas.yaml with something like:

sgeorgia300b:
  description: Iceberg A-68a (OLCI Sentinel-3A/3B)
  projection:
    proj: stere
    ellps: WGS84
    lat_0: -56.00
    lon_0: -36.00
  shape:
    height: 2000
    width: 2000
  area_extent:
    lower_left_xy: [-270000.0, -270000.0]
    upper_right_xy: [270000.0, 270000.0]

A result from today using this area is attached. Shape must always be in sync with area_extent and resolution of the instrument in use at SSP. Stere is conformal, grid lines must cross at 90°.

Cheers,
Ernst


Ferdinand Valk
 

Ernst,

 

Thanks for the details. I had already moved east and changed to landscape format here, but your suggestion is very useful.

Today the Copernicus hub was unavailable most of the time and so only now I got today’s data.

S1A_EW_GRDM_1SSH_20201222T071734_20201222T071834_035795_0430AC_13DF.SAFE

The crop above shows that the fault line I expected to rupture did precisely that today. A disconnect of the finger is clearly visible as well as the separation of the knuckles. Things unfold really fast!

 

Cheers,

Ferdinand

 

From: MSG-1@groups.io On Behalf Of Ernst Lobsiger via groups.io
Sent: Tuesday, 22 December, 2020 21:18
To: MSG-1@groups.io
Subject: Re: [MSG-1] A-68A turning again.

 

Ferdinand,
Users of my Sentinel-3A/B scripts,

an exeptional Sentinel-3B image from A68a today. It seems the iceberg will leave the sgeorgia300 area soon. The easiest way to follow will be an update of the personal areas.yaml with something like:
//snip

 


geojohnt@...
 

Hello Ferdinand,

Another great image, thanks.

I'm surprised, I think, given the size of this iceberg and its vicinity, that we haven't seen any 'ground based' photos from ships or surveillance aircraft.

OK it's a remote part of the ocean but this is a big iceberg.

Regards,
John.

+++++++++++++++++++++++


-----Original Message-----
From: Ferdinand Valk <fvalk@...>
To: MSG-1@groups.io
Sent: Tue, 22 Dec 2020 16:18
Subject: Re: [MSG-1] A-68A turning again.

Yes John, that is correct. The fault line I refer to in the sar image is the same as the black line you see in your Metop and also in the attached Sentinel 3B image of today. The black in the colour image is the surface melt filling up the crack: this is the principal reason to suspect this line to give way first.
 
From: MSG-1@groups.io On Behalf Of geojohnt via groups.io
Sent: Tuesday, 22 December, 2020 15:42
To: MSG-1@groups.io
Subject: Re: [MSG-1] A-68A turning again.
 
Hello Ferdinand,
 
Thanks for the amazing image.
Such incredible detail and as you say bits floating nearby having broken off.
 
I agree about the cloud edge shadow line but enlarging todays Metop image to 300% although blurred appears to show(?) a black crack/line/area - which again could be shadow - at the base area of the finger, but it seems to correspond to the fault line in your image?
 
Regards,
John.

++++++++++++++++++++++++++
-----Original Message-----
From: Ferdinand Valk <fvalk@...>
To: MSG-1@groups.io
Sent: Tue, 22 Dec 2020 14:25
Subject: Re: [MSG-1] A-68A turning again.
There is indeed some calving at the pointed tip. Bits can be seen floating nearby. The line you see across the centre is caused by cloud. Most of the fault lines visible in the sar imagery run lengthwise through the slab; there is one major fault though at the root of the pointing finger that may well be the first to rupture.
 
Ferdinand
 
From: MSG-1@groups.io On Behalf Of geojohnt via groups.io
Sent: Tuesday, 22 December, 2020 12:55
To: msg-1@groups.io; geo-subscribers@groups.io
Subject: [MSG-1] A-68A turning again.
 
All,
 
Todays Metop image via EUMETCast shows the iceberg rotating again.
And, is the pointed bit breaking away?
 
Not sure about the line across the centre of the iceberg - cloud edge shadow?
 
Regards,
John.


Ernst Lobsiger
 

John and Ferdinand,

while John noticed the first crack accross the A68a finger (on a Metop image!!) and Ferdinand added a final Sentinel-1A SAR-C measurement *.tiff confirmation,
I was unable to read the same GRDM file with Pytroll/Satpy because it only contained hh data. I have fixed that now by adding two homebrew sar-c composites.

Cheers,
Ernst


Ferdinand Valk
 

Ernst,

 

Excellent. Does that mean that you have found a solution to single versus dual polarization (SSH / SDH) issue in Pytroll/Satpy? Or do you mean with homebrew that you solved it outside of Satpy?

 

I couldn’t get single (hh) to work thus far.

 

Cheers,

Ferdinand

 

From: MSG-1@groups.io On Behalf Of Ernst Lobsiger via groups.io
Sent: Thursday, 24 December, 2020 14:24
To: MSG-1@groups.io
Subject: Re: [MSG-1] A-68A turning again.

 

John and Ferdinand,

while John noticed the first crack accross the A68a finger (on a Metop image!!) and Ferdinand added a final Sentinel-1A SAR-C measurement *.tiff confirmation,
I was unable to read the same GRDM file with Pytroll/Satpy because it only contained hh data. I have fixed that now by adding two homebrew sar-c composites.

Cheers,
Ernst


Ernst Lobsiger
 

On Thu, Dec 24, 2020 at 08:06 AM, Ferdinand Valk wrote:
Excellent. Does that mean that you have found a solution to single versus dual polarization (SSH / SDH) issue in Pytroll/Satpy?
Ferdinand,

TBH I'am not a composite guru at all. Christian Peters is quite experienced in this field. But yes, it's inside Satpy for SSH. I make some latest tests for the absolute minimum you have to do
(files you have to copy into your personal pppconfig) to make it work. Then I will publish my solution here. The latest Satpy documetation is still somewhat hard to read in this field. Stay tuned!

Regards,
Ernst


Ferdinand Valk
 

Great, I’m sitting at attention!

 

From: MSG-1@groups.io On Behalf Of Ernst Lobsiger via groups.io
Sent: Thursday, 24 December, 2020 16:23
To: MSG-1@groups.io
Subject: Re: [MSG-1] A-68A turning again.

//

But yes, it's inside Satpy for SSH. I make some latest tests for the absolute minimum you have to do (files you have to copy into your personal pppconfig) to make it work. Then I will publish my solution here. The latest Satpy documetation is still somewhat hard to read in this field. Stay tuned!

Regards,
Ernst

 


Ernst Lobsiger
 

On Thu, Dec 24, 2020 at 08:06 AM, Ferdinand Valk wrote:
I couldn’t get single (hh) to work thus far.
Ferdinand,

it works like areas.yaml. This file takes precedence over the file areas.yaml in Satpy's 'etc' directory. In 'etc' there are subdirectories 'composites' and 'enhancements'.
There you find all current configurations built in. You can make the same subdirectories in your pppconfig and store your extra stuff there. I attach what I had to add
as a bare minimum to make 'hh' and 'hv' work for B&W images. This means you can also image single channels from an SDH file like the one from yesterday. Along
these lines it should be easy to make composites for 'vv' or 'vh' but also other dual combinations in SAR-C *.SAFE files. Have fun ...



Cheers,
Ernst


Ferdinand Valk
 

Thanks Ernst. Will get working with it and for sure have fun.

 

From: MSG-1@groups.io On Behalf Of Ernst Lobsiger via groups.io
Sent: Thursday, 24 December, 2020 17:42
To: MSG-1@groups.io
Subject: Re: [MSG-1] A-68A turning again.

 

On Thu, Dec 24, 2020 at 08:06 AM, Ferdinand Valk wrote:

I couldn’t get single (hh) to work thus far.

Ferdinand,

it works like areas.yaml. This file takes precedence over the file areas.yaml in Satpy's 'etc' directory. In 'etc' there are subdirectories 'composites' and 'enhancements'.
There you find all current configurations built in. You can make the same subdirectories in your pppconfig and store your extra stuff there. I attach what I had to add
as a bare minimum to make 'hh' and 'hv' work for B&W images. This means you can also image single channels from an SDH file like the one from yesterday. Along
these lines it should be easy to make composites for 'vv' or 'vh' but also other dual combinations in SAR-C *.SAFE files. Have fun ...



Cheers,
Ernst


Ferdinand Valk
 

Ernst,

 

I had a chance to work with your suggestions and it works perfectly well. A first result is seen here: A68 (fvalk.com)

It seems that the next rupture will be lengthwise through the middle of A68 and that the pieces will soon bend around the southern tip of the elevated sea floor to continue north/northeast.

 

Cheers,

Ferdinand

 

 

From: MSG-1@groups.io On Behalf Of Ernst Lobsiger via groups.io
Sent: Thursday, 24 December, 2020 17:42
To: MSG-1@groups.io
Subject: Re: [MSG-1] A-68A turning again.

 

On Thu, Dec 24, 2020 at 08:06 AM, Ferdinand Valk wrote:

I couldn’t get single (hh) to work thus far.

Ferdinand,

it works like areas.yaml. This file takes precedence over the file areas.yaml in Satpy's 'etc' directory. In 'etc' there are subdirectories 'composites' and 'enhancements'.
There you find all current configurations built in. You can make the same subdirectories in your pppconfig and store your extra stuff there. I attach what I had to add
as a bare minimum to make 'hh' and 'hv' work for B&W images. This means you can also image single channels from an SDH file like the one from yesterday. Along
these lines it should be easy to make composites for 'vv' or 'vh' but also other dual combinations in SAR-C *.SAFE files. Have fun ...
//snip


Ernst Lobsiger
 

On Fri, Dec 25, 2020 at 04:50 AM, Ferdinand Valk wrote:
I had a chance to work with your suggestions and it works perfectly well.
Ferdinand,

With my 16GB RAM PC I managed to read and display the GRDH IW file from South Georgia. I simply made a vv 'composite' and did not reproject but simply write out the groundrange.
Original image size 214MB, 28625 x 20138 pixels,16Bit. I had to flop the image left/right to make it look the way we are used to. For this IM was handy. Just did "convert SB1.png -flop ...".

Cheers,
Ernst

P.S. I will try to make color composites (vv vh) on my 24GB RAM PC.


Ferdinand Valk
 

Ernst,

 

It must have taken quite a load and processing time to do the ‘H’ file on 16GB of RAM, but I’m happy you managed.

I have all versions (hh, hv, vh, vv) working here, as well as the SDH, SSH and SDV plus EW and IW, and all remapping. If you would manage also to get colour out of the them it would be complete I believe. The next thing I would like to tackle (given time and energy) is the SLC, which is a concatenation of sub-images within a long strip.

I really don’t understand why I didn’t start pytroll/satpy much before.

 

Cheers,

Ferdinand

 

From: MSG-1@groups.io On Behalf Of Ernst Lobsiger via groups.io
Sent: Saturday, 26 December, 2020 20:41
To: MSG-1@groups.io
Subject: Re: [MSG-1] A-68A turning again.

 

On Fri, Dec 25, 2020 at 04:50 AM, Ferdinand Valk wrote:

I had a chance to work with your suggestions and it works perfectly well.

Ferdinand,

With my 16GB RAM PC I managed to read and display the GRDH IW file from South Georgia. I simply made a vv 'composite' and did not reproject but simply write out the groundrange.
Original image size 214MB, 28625 x 20138 pixels,16Bit. I had to flop the image left/right to make it look the way we are used to. For this IM was handy. Just did "convert SB1.png -flop ...".

Cheers,
Ernst

P.S. I will try to make color composites (vv vh) on my 24GB RAM PC.

//


Ernst Lobsiger
 

On Sun, Dec 27, 2020 at 03:46 AM, Ferdinand Valk wrote:
I really don’t understand why I didn’t start pytroll/satpy much before.
Ferdinand,

The color is easy as well ( 'sar-ice-legacy-iw' did crash even my 24GB PC). In the original ..etc/composites/sar.yaml there already is a 'sar-ice-iw' composite.
You can copy  'sar-quick' etc. to your personal pppconfig/composites/sar.yaml and rename it  'sar-quick-iw' but leave the standard name 'sar-quick'. That's all.
Nothing to do in the enhancements. These are used as before from Satpy's own generic.yaml file.





Have more fun
Ernst


Ferdinand Valk
 

Ernst,

 

I had myself concocted already something before, but that came out as the attached image. I will try the -iw.

 

Ferdinand

 

From: MSG-1@groups.io On Behalf Of Ernst Lobsiger via groups.io
Sent: Sunday, 27 December, 2020 13:12
To: MSG-1@groups.io
Subject: Re: [MSG-1] A-68A turning again.

Ferdinand,

The color is easy as well ( 'sar-ice-legacy-iw' did crash even my 24GB PC). In the original ..etc/composites/sar.yaml there already is a 'sar-ice-iw' composite.
You can copy  'sar-quick' etc. to your personal pppconfig/composites/sar.yaml and rename it  'sar-quick-iw' but leave the standard name 'sar-quick'. That's all.
Nothing to do in the enhancements. These are used as before from Satpy's own generic.yaml file.
//


Ernst Lobsiger
 

Ferdinand,

... and of course in the copied and *-iw renamed composites you have to edit the channels to 'vv' and 'vh'.

Ernst


Ferdinand Valk
 

Understood

 

From: MSG-1@groups.io On Behalf Of Ernst Lobsiger via groups.io
Sent: Sunday, 27 December, 2020 13:32
To: MSG-1@groups.io
Subject: Re: [MSG-1] A-68A turning again.

 

Ferdinand,

... and of course in the copied and *-iw renamed composites you have to edit the channels to 'vv' and 'vh'.

Ernst