The land sea mask used in the ECMWF IFS changed with the introduction of 41R1. Figures in the table below illustrate where there have been changes (please refer to the title on each image). Mostly the changes were for the better, with some notable improvements over Europe (mostly the land area is now bigger - row 9 below shows an example). However there were also some areas of degradation, specifically in the Pacific, where some islands have unfortunately 'disappeared' due to errors in the new reference geographical dataset - all . All known instances of disappearing islands are shown on the following tableincluded below, in rows 2-7. Locations of these are also marked on the global map 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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