fls_sat_verif

Satellite-based verification of fog and low stratus forecasts. For explanation of underlying ideas see the following two publications and a dedicated confluence page:

• https://doi.org/10.1002/qj.3849 : Sections 3.1 and 5.1
• https://doi.org/10.1029/2020MS002437 : Section 3.2
• https://service.meteoswiss.ch/confluence/x/OpJGBg

Installation

1. Clone this repo
2. cd fls_sat_verif
3. make venv install

If you are a developer, you might want to install the package as an editable: make venv install-dev

Usage

You might want to copy and modify the test script (see next section) which runs the verification according to the steps described below.

All work will happen in a dedicated working directory <wd>, e.g. $SCRATCH/wd_fls_sat_verif.

To get detailed log-messages printed to screen use -v, -vv or even -vvv.

1. Prepare SAT input data: Retrieve with rubyscript

1. Create directory <wd>/sat

2. Run: rbrun ~osm/bin/extract_satdata.rb -P LSCL -m c1e -p <start>..<end>,1h -o <wd>/sat/ -v

   • start: e.g. 202108302345
   • end: e.g. 202112312345
   • intervall: 1h, 3h

   ! The satellite files are available at :45 only!

3. Manually check whether files are available, if many files are missing, get in contact with Uli Hamann & Daniel Leuenberger

2. Prepare COSMO input data: Retrieve from archive, extract TQC

IMPORTANT! Expected model output format: <exp_dir>/FCST<YY>/YYMMDDHH_???/grib/c1effsurfHHH_000. You might need to create a link for <exp_dir>/FCST<YY> depending on the structure of your data.

conda activate fls_sat_verif

fls_sat_verif --retrieve_cosmo --wd <wd> --start <YYMMDDHH> --end <YYMMDDHH> --interval <HH> --exp_model_dir <exp_dir> --exp <experiment_identifier> --model c1e

ADVICE! If you evaluate a long period, cut it into chunks of 3-5 days and send parallel jobs on postproc nodes with sbatch or batchPP.

3. Calculate FLS fractions

fls_sat_verif --calc_fractions --wd <wd> --start <YYMMDDHH> --end <YYMMDDHH> --interval <HH> --max_lt <HH> --exp <experiment_name> --extend_previous --model c1e

4. Plotting

fls_sat_verif --plot_median_day_cycle --wd <wd> --start <YYMMDDHH> --end <YYMMDDHH> --init <H> --exp <experiment_name>

fls_sat_verif --plot_fraction_per_leadtime --wd <wd> --start <YYMMDDHH> --end <YYMMDDHH> --max_lt <LT> --init <H> --exp <experiment_name>

Test

At the moment there is one test script included which tests the processing chain for a cosmo-2e experiment. If no "succesfull" is printed at the end, the test has failed. First activate your conda environment and then run:

./tests/fls_sat_verif/test_fls_sat_verif.sh

Credits

This package was created with Cookiecutter and the MeteoSwiss-APN/mch-python-blueprint project template.