Processing notebook, data_preparation corrections and adjust_radar draft

[EliaCovi]

• Added processing notebooks as described in Add notebook with CML processing open OpenMRG and OpenRainER CML data #6
• Minor modification to 1_data_preparation.ipynb after OpenRainER update.
• 1_data_preparation.ipynb was changed to consider only two month of OpenRainER
• Added 3_adjust_radar.ipynb based on update and rerun radar-CML merging notebook with final workflow #7

[cchwala]

Thanks for moving this forward. Please comment here once you think this PR is ready to merge.

[EliaCovi]

Thanks for moving this forward. Please comment here once you think this PR is ready to merge.

I think it's ready. I decided to add in this PR the first draft of 3_adjust_radar (if it's too early I'll try to remove it).

[cchwala]

Yes, that is perfect. I had a quick look at the notebook 3 with the radar adjustment and it is good, but as far as I see the results for OpenRainER are not yet good, for CMLs... So we should iterate things further. For now, it is great to have the full consistent workflow with notebook 1, 2 and 3 💪.

This will close #6

We can also close #7 and open a new issue to discuss, and potentially improve, the OpenRainER merging results.

[cchwala]

...and potentially improve, the OpenRainER merging results.

As discussed via chat, the current results for OpenRainER are using gauge-adjusted radar, hence, the radar data fits the gauges very good. @EliaCovi will switch to unadjusted radar soon and the radar-CML adjustment should then show the expected results. So, nothing to worry currently.