CEMS-Flood data comes primarily in GRIB2 format.
The easiest way to To read GRIB file is through Python using files we encourage using Python and the xarray's CFGRIB engine. The following instructions assume
Follow the instructions below to install the required libraries, assuming you are working on a Linux machineOS.
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First of all install Conda, a Python packages and environments manager, from https://docs.conda.io/projects/conda/en/latest/index.html.
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Then open a terminal and type:
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# create a local virtual environment, you can call it as you wish, here 'myenv' is used. conda create -n myenv python=3.8 # add repository channel conda config --add channels conda-forge # activate the local environment. conda activate myenv # install the required packages conda install -c conda-forge/label/main xarray cfgrib eccodes |
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# make sure you have installed eccodes version >= 2.23.0
python -c "import eccodes; print(eccodes.__version__)" |
Start a python console (it is important that you have activated the local environment) and type:
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# assumed you have download from the Climate Data Store a GloFAS GRIB file named 'download.grib'
In [1]: import xarray as xr
# reading GloFAS GRIB file
In [2]: ds = xr.open_dataset('download.grib',engine='cfgrib')
In [3]: ds
Out[4]:
<xarray.Dataset>
Dimensions: (latitude: 1500, longitude: 3600, step: 3, time: 3)
Coordinates:
number int64 ...
* time (time) datetime64[ns] 2019-12-01 2019-12-02 2019-12-03
* step (step) timedelta64[ns] 1 days 2 days 3 days
surface int64 ...
* latitude (latitude) float64 89.95 89.85 89.75 ... -59.75 -59.85 -59.95
* longitude (longitude) float64 -179.9 -179.8 -179.8 ... 179.7 179.8 179.9
valid_time (time, step) datetime64[ns] ...
Data variables:
dis24 (time, step, latitude, longitude) float32 ...
Attributes:
GRIB_edition: 2
GRIB_centre: ecmf
GRIB_centreDescription: European Centre for Medium-Range Weather Forecasts
GRIB_subCentre: 0
Conventions: CF-1.7
institution: European Centre for Medium-Range Weather Forecasts
history: 2021-02-11T11:00:21 GRIB to CDM+CF via cfgrib-0.... |
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