Collocate SEVIRI L1B HRIT

[danielphilipp]

Hi Nina,

we are planning to do some neural network applications where we need SEVIRI L1B collocations with CALIPSO layered data. I wrote some external code reading SEVIRI L1B HRIT data with satpy and putting them into the correct format (class structure) for atrain_match functionalities. To run the collocations only some atrain_match functions are called producing matchup files with the L1B measurements. It is working pretty good so far. In fact there are only minor changes needed to one function within atrain_match itself to get the whole thing working.

Before going into the details ... Would you be interested to have this functionality within atrain_match ?

The whole L1B handling stuff would be kept external.

Cheers,
Daniel

[ninahakansson]

Hi @danielphilipp,

Yes, I think that will be very good to have in atrain_match! Currently SEVIRI data need to be read from PPS level1c but it makes sense to be able to use the L1B directly. Are you using satpy to read the HRIT data?

[danielphilipp]

Hi @ninahakansson,

nice to hear. I will prepare a PR within the next days so you can see the changes needed to atrain_match.

Yes, I use satpy to get SEVIRI measurements and lat/lon.

solzen is calculated with pyorbital.astronomy and satzen is read from the CLAAS2 auxfile but in the future I will also calculate it on-the-fly to remove the dependency on the CLAAS2 auxfile .. or make it optional.

[ninahakansson]

Thanks @danielphilipp looking forward to the PR!

In level1c4pps (https://github.com/foua-pps/level1c4pps) we also use satpy and pyorbital to read and calculate angles. In seviri2pps_lib.py there is a get_satellite_angles that might do what you need.

[danielphilipp]

Yes that is exactly what I need, thank you :)