FG departures of for 2D-OI (2m temperature, relative humidity and snow depth analysis) are calculated in fg2obs.F90. At first, observations are sorted by OBS_RAWTABLE(jpraw_refcoord, jtotal) based on latitude and longitude (prepared in scan_cma_odb.F90).
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However, latitude is rounded down to the second decimal place when OBS_RAWTABLE(jpraw_refcoord, jtotal) is calculated. As a resultsresult, the indexes indices are sometimes not in ascending order precisely and the FG departures are not calculated from surrounded 4 model grids. The following table shows the an example. ZOBSLAT should be at the latitude between ALAT(jlatN) and ALAT(jlatS) but it is not there (at the south side of ALAT(jlatS)).
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