Pytroll/Satpy help on .py file


Daniele Guardigli
 

Hello,

I'm sorry for my ignorance in Python language! Can anyone help me on setting 'airmass' scene on MSG4.py script? Seems it's not available but it's very useful during night and day.

Thank you!

Daniele Guardigli


Ernst Lobsiger
 

Daniele,


MSG seviri instrument has these channels:

# Channel | VIS006 |   HRV  | VIS008 | IR_016 | IR_039 | WV_062 |
# WaveLen |  0.635 |   0.7  |   0.81 |   1.64 |   3.90 |   6.25 |
# --------+--------+--------+--------+--------+--------+--------+
# Channel | WV_073 | IR_087 | IR_097 | IR_108 | IR_120 | IR_134 |
# WaveLen |   7.35 |   8.70 |   9.66 |  10.80 |  12.00 |  13.40 |


Satpy composite definition of 'airmass':
...
  airmass:
    compositor: !!python/name:satpy.composites.GenericCompositor
    prerequisites:
    - compositor: !!python/name:satpy.composites.DifferenceCompositor
      prerequisites:
      - wavelength: 6.2
      - wavelength: 7.3
    - compositor: !!python/name:satpy.composites.DifferenceCompositor
      prerequisites:
        - wavelength: 9.7
        - wavelength: 10.8
    - wavelength: 6.2
    standard_name: airmass
...


You need two more 'airmass' lines in your script, put it like below:

...
# We only decompress what is actually needed, see file seviri.yaml
needed_files = {'overview'         : ['VIS006', 'VIS008', 'IR_108'],
                'natural_color'    : ['VIS006', 'VIS008', 'IR_016'],
                'realistic_colors' : ['VIS006', 'VIS008', 'HRV'],
                'hrv_clouds'       : ['IR_108', 'HRV'],
                'night_fog'        : ['IR_039', 'IR_108', 'IR_120', 'IR_134'],
                'airmass'          : ['WV_062', 'WV_073', 'IR_097', 'IR_108'],
                'ir108_3d'         : ['IR_108']}
# Some composite names are too long for IM annotation left of pic
abbreviation = {'overview'         : 'overview',
                'natural_color'    : 'natural_color',
                'realistic_colors' : 'realist_color',
                'hrv_clouds'       : 'hrv_clouds',
                'night_fog'        : 'night_fog',
                'airmass'          : 'airmass',
                'ir108_3d'         : 'ir108_3d'}
...

Then set composite='airmass' and run the script ...


Hope this helps,

Ernst


Daniele Guardigli
 

It works!!! Thank you very much Ernst for your patience


Il giorno lun 11 ott 2021 alle ore 15:53 Ernst Lobsiger via groups.io <ernst.lobsiger=belponline.ch@groups.io> ha scritto:
Daniele,


MSG seviri instrument has these channels:

# Channel | VIS006 |   HRV  | VIS008 | IR_016 | IR_039 | WV_062 |
# WaveLen |  0.635 |   0.7  |   0.81 |   1.64 |   3.90 |   6.25 |
# --------+--------+--------+--------+--------+--------+--------+
# Channel | WV_073 | IR_087 | IR_097 | IR_108 | IR_120 | IR_134 |
# WaveLen |   7.35 |   8.70 |   9.66 |  10.80 |  12.00 |  13.40 |


Satpy composite definition of 'airmass':
...
  airmass:
    compositor: !!python/name:satpy.composites.GenericCompositor
    prerequisites:
    - compositor: !!python/name:satpy.composites.DifferenceCompositor
      prerequisites:
      - wavelength: 6.2
      - wavelength: 7.3
    - compositor: !!python/name:satpy.composites.DifferenceCompositor
      prerequisites:
        - wavelength: 9.7
        - wavelength: 10.8
    - wavelength: 6.2
    standard_name: airmass
...


You need two more 'airmass' lines in your script, put it like below:

...
# We only decompress what is actually needed, see file seviri.yaml
needed_files = {'overview'         : ['VIS006', 'VIS008', 'IR_108'],
                'natural_color'    : ['VIS006', 'VIS008', 'IR_016'],
                'realistic_colors' : ['VIS006', 'VIS008', 'HRV'],
                'hrv_clouds'       : ['IR_108', 'HRV'],
                'night_fog'        : ['IR_039', 'IR_108', 'IR_120', 'IR_134'],
                'airmass'          : ['WV_062', 'WV_073', 'IR_097', 'IR_108'],
                'ir108_3d'         : ['IR_108']}
# Some composite names are too long for IM annotation left of pic
abbreviation = {'overview'         : 'overview',
                'natural_color'    : 'natural_color',
                'realistic_colors' : 'realist_color',
                'hrv_clouds'       : 'hrv_clouds',
                'night_fog'        : 'night_fog',
                'airmass'          : 'airmass',
                'ir108_3d'         : 'ir108_3d'}
...

Then set composite='airmass' and run the script ...


Hope this helps,

Ernst



--
Daniele Guardigli