[Python] Xarray (from grib file) to dataset

I have a grib file containing monthly precipitation and temperature from 1989 to 2018 (extracted from ERA5-Land).

I need to have those data in a dataset format with 6 column : longitude, latitude, ID of the cell/point in the grib file, date, temperature and precipitation.

I first imported the file using cfgrib. Here is what contains the xdata list after importation:

import cfgrib

grib_data = cfgrib.open_datasets('\era5land_extract.grib')

grib_data
Out[6]:
[<xarray.Dataset>
Dimensions: (latitude: 781, longitude: 761, time: 372)
Coordinates:
number int32 0
* time (time) datetime64[ns] 1989-01-01 1989-02-01 ... 2019-12-01
step timedelta64[ns] 1 days
surface float64 0.0
* latitude (latitude) float64 42.0 41.9 41.8 41.7 ... -35.8 -35.9 -36.0
* longitude (longitude) float64 -21.0 -20.9 -20.8 -20.7 ... 54.8 54.9 55.0
valid_time (time) datetime64[ns] ...
Data variables:
t2m (time, latitude, longitude) float32 ...
Attributes:
GRIB_edition: 1
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,
<xarray.Dataset>
Dimensions: (latitude: 781, longitude: 761, time: 156)
Coordinates:
number int32 0
* time (time) datetime64[ns] 1989-01-01 1989-02-01 ... 2001-12-01
step timedelta64[ns] 1 days
surface float64 0.0
* latitude (latitude) float64 42.0 41.9 41.8 41.7 ... -35.8 -35.9 -36.0
* longitude (longitude) float64 -21.0 -20.9 -20.8 -20.7 ... 54.8 54.9 55.0
valid_time (time) datetime64[ns] ...
Data variables:
tp (time, latitude, longitude) float32 ...
Attributes:
GRIB_edition: 1
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,
<xarray.Dataset>
Dimensions: (latitude: 781, longitude: 761, time: 216)
Coordinates:
number int32 0
* time (time) datetime64[ns] 2002-01-01 2002-02-01 ... 2019-12-01
step timedelta64[ns] 1 days
surface float64 0.0
* latitude (latitude) float64 42.0 41.9 41.8 41.7 ... -35.8 -35.9 -36.0
* longitude (longitude) float64 -21.0 -20.9 -20.8 -20.7 ... 54.8 54.9 55.0
valid_time (time) datetime64[ns] ...
Data variables:
tp (time, latitude, longitude) float32 ...
Attributes:
GRIB_edition: 1
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]


So the temperature variable is called "t2m" and the precipitation variable "tp". Precipitaion variable is split in two xarrays but I don't understand why.

How can I obtain the needed dataset from this please ?

It's the first time I'm dealing with such data, and I'm really lost on how to proceed.

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