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Metview's GRIB Filter icon has parameters which enable the interpolation of data onto a new grid, or the extraction of a sub-area. This can be useful if you wish to compare two fields which are currently at different resolutions (e.g. from different model runs) - both fields need to be on the same grid before Metview can perform computations between them.
The GRIB icon reduced_gg_320 contains one field which is stored as a reduced Gaussian grid. Visualise the U wind field (via the GRIB Filter icon you created earlier) and apply the gridpoints icon (in the solutions folder) to display the locations of the grid points - they are on a regular 1.5 degree grid.
Now create a new GRIB Filter icon with these parameters:
| Data | Drop the reduced_gg_320 u GRIB Filter icon here |
| Grid | 2.5/2.5 |
The result will be the same data interpolated onto a 2x2 2.5x2.5 degree grid. Visualise the result and apply the gridpoints icon to confirm the new grid. Visualise the two fields side-by-side with coloured contour shading to also confirm that they look very similar in terms of their data values.
Sub-area Extraction from a fieldset
The GRIB Filter icon also allows the extraction of a sub-area from a fieldset.Create a new one and, using the Area parameter, extract just the data over a selected region for a given GRIB file.
Conversion Between Points and Fields
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