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In Metview 4, the default behaviour is to always overlay fields from different sources, even if their meta-data, such as date/time, do not match. This is different from Metview 3, whose default behaviour was to only overlay data whose timestamps 'match'. In Metview 3, there was a separate icon, the Overlay Control icon, which could be dropped into a View icon to change the overlay settings. In Metview 4 this is simpler, with a Map Overlay Control parameter directly in the Geographical View icon. See Data Overlay for more information.
Cross Section Data, Average Data, Hovmoeller Data
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