Orographic correction

[ArcticSnow]

Here are few references collected on method to perform orographic corrections based on terrain:

• read Smith and Barstad 2004, https://journals.ametsoc.org/view/journals/atsc/61/12/1520-0469_2004_061_1377_altoop_2.0.co_2.xml
• read Thomas paper as well as Aurora
• talk to Andy beaucse of: https://github.com/pism/LinearTheoryOrographicPrecipitation
• Thomas' Matlab implementation from ERA5: https://github.com/TVSchuler/Sval_Imp_matlab/blob/0088e31877334428cddcb4ff9b87bcb3973c4bbb/precipitation/LT_matlab_2016_09_16.m#L126
• For validation, we could check against ERA5 Land, or CARRA in Svalbard