The land sea mask used in the ECMWF IFS changed with the introduction of 41R1. Figures in the table below are examples of where there have been changes (for colour meaning refer to the image titles, all are consistent). Mostly the changes were for the better, with some notable improvements over Europe†. Unfortunately however there have also been some areas of degradation, specifically in the Pacific, where some islands have unfortunately 'disappeared' due to errors in the new reference geographical dataset. All known instances of disappearing islands are included below, in rows 2-7. It is mainly HRES that is affected. Locations of these plots are also marked on the global maps on row 1. Following consultation it was decided to wait until the next cycle (41R2) before these errors are rectified. Row 8 illustrates that there have also been some significant changes in the land and sea points around Antarctica.
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