| Info | ||
|---|---|---|
| ||
While addressing a sub-optimal performance issue for interpolation from the octahedral reduced Gaussian grid introduced with IFS cycle 41r2 to regular latitude-longitude grids, a problem was discovered with the method used to calculate the longitudinal points in the source grid. In some specific cases, this problem leads to an incorrect computation of interpolation weights and hence to incorrect interpolated values at some points of the output grid. The problem affects all versions of EMOSLIB prior to version 4.3.0. The problem is also present in fields retrieved with versions of MARS (including the WebAPI) that use any EMOSLIB version prior to cycle 000430, version 4.3.0, Metview versions prior to 4.6.1 and for disseminated products from IFS cycle 41r1 and earlier. This page provides information about the problem and the specific cases where differences can occur. |
...
In addition, the problem is fixed for interpolations from original reduced or octahedral reduced Gaussian grids to sub-areas of unrotated regular Gaussian grids or regular lat-lon grids at EMOSLIB 4.3.67.
For which cases does the problem still exist ?
...
The problem is fixed in EMOSLIB cycle version 4.3.6 7 and newer. This is used by:
- MARS client to be updated in February 2016 (until then it is available with "mars -t")
- Metview version 4.6.3 4 and newer
- Disseminated products for IFS cycle 41r2 (implementation planned for March 2016)
...