Invalid netcdf provided by weatherprediction function

The three 'future' datasets provided by the smart monitoring backend module ('Future Solar Radiation', 'Future Soil Temperature', 'Future Wind Speed') via the 'weatherprediction' function are invalid. They only provide x and y dimensions, but missing a proper CRS specification in the global attributes.

Possible solutions:

1. in case the x/y dimensions are in EPSG:4326 projection, label the dimensions lon/lat, or
2. in case it's a different projection provide the corresponding epsg code in a 'crs' property of the global attributes.

Furthermore, but not crucial, the variable has no name, so the xarray to netcdf function (used to serialize/encode the dataset) sets the name of the variable to __xarray_dataarray_variable__. This string is used in the layer switcher to inform the user about the attribute that is currently shown. So, if possible set the variable's name property to a meaningful value, e.g. 'solar_radiation'.