Documentation on how to find shapefiles for hydrology recipes

[JaroCamphuijsen]

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Please discuss your idea with the development team before getting started, to avoid disappointment later. The way to do this is to open a new issue on GitHub. If you are planning to modify an existing functionality, please discuss it with the original author(s) by tagging them in the issue.

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Tasks

• Create an issue to discuss what you are going to do, if you haven't done so already (and add the link at the bottom)
• Give this pull request a descriptive title that can be used as a one line summary in a changelog
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• Please use yamllint to check that your YAML files do not contain mistakes
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New recipe/diagnostic

• Add documentation for the recipe to the doc/sphinx/source/recipes folder and add a new entry to index.rst
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Modified recipe/diagnostic

• Update documentation for the recipe to the doc/sphinx/source/recipes folder
• Update provenance information if needed
• Assign the author(s) of the affected recipe(s) as reviewer(s)

New data reformatting script

• Test the CMORized data using recipes/example/recipe_check_obs.yml, to make sure the CMOR checks pass without errors
• Add the new dataset to the table in the documentation
• Tag @mattiarighi in this pull request, so that the new dataset can be added to the OBS data pool at DKRZ and synchronized with CEDA-Jasmin

Modified data reformatting script

• Test the CMORized data using recipes/example/recipe_check_obs.yml, to make sure the CMOR checks pass without errors
• Tag @mattiarighi in this pull request, so that the updated dataset can be added to the OBS data pool at DKRZ and synchronized with CEDA-Jasmin

If you need help with any of the tasks above, please do not hesitate to ask by commenting in the issue or pull request.

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Closes #1762

[SarahAlidoost]

@JaroCamphuijsen Thank you, I suggested some minor revisions.

[JaroCamphuijsen]

@bouweandela can you merge this?