res_conservative_interpolations

To come back to the upper stage

COMPARISON OF THE RESULTS OBTAINED WITH OASIS3 (using the librairy SCRIP) IN MODE INTERPOLATOR (in monoprocessor)
(https://verc.enes.org/models/software-tools/oasis) FOR DIFFERENT IMPLEMENTATION OF THE NORMALISATION OF THE CONSERVATIVE
INTERPOLATION.

The parameter north_tresh is equal to 2 rad so there is no projection
for the cells located above this latitude in a plan conatining the pole.

The results are presented in the table below. For each couple of grids, different options and implementations of the conservative interpolation are tested:
fracnnei : if all neighbour source cells are masked, the value of the flux of the nearest unmasked source cell is used to calculate the value at the target cell.
fracnntr : if all neighbour source cells are masked, the value of the flux of the nearest unmasked source cell is used to calculate the value at the target cell,
the normalisation of the weights is done using the true areas (ie calculated by the models) of the source and the target grid.
The interpolated field correponds to the analytical function f1 :

For each interpolation, the source field, the target field and the error field are presented. The points at -3 correspond to the masked points.
The points at 0 correspond to points in the target field that do not receive any value.

The results were obtained on a Linux PC for BT42-orca2T, on Corail (CERFACS, HP ADM Cluster) for T359-orca025T interpolations, and on
Napali for T799-orca025T interpolations.

The cells that overlap are masked for orca2T and orca025T.

RESOLUTIONS : BT42 = 6232x1x1 ; ORCA2 = 182x149x1 ; ORCA025 = 1442x1021x1 ; ARPEGE RED T359 = 181724x1 ; ARPEGE RED T799 = 843490x1

Interpolations Couples of Grids	CONSERVATIVE INTERPOLATION 2D official version fracnnei	CONSERVATIVE INTERPOLATION 2D new version fracnnei	CONSERVATIVE INTERPOLATION 2D new version fracnntr
ORCA2T / BT42	f1	f1 diff fracnnei_new/fracnnei_old	f1 diff fracnntr_new/fracnnei_new
BT42 / ORCA2T	f1	f1 diff fracnnei_new/fracnnei_old	f1 diff fracnntr_new/fracnnei_new
ORCA025 T / T359			f1
T359 / ORCA025 T			f1
ORCA025 T / T799			f1
T799 / ORCA025T			f1