Fig. 2

Global map showing the distribution of the training set used to map the global distribution of tidal flats between 60°N to 60°S. (a) Training set annotated with class ‘Other’. (b) Training set annotated with class ‘Permanent water’. (c) Training set annotated with class ‘Tidal flat’. The figure shows that training data was collected along the entire global coastline, though training samples for tidal flat are naturally concentrated in areas where tidal flats occur. The bounding box of the analysis is shown with a bold dashed line. Note maps show training data used for Version 1.2 of the tidal flat maps (n = 14,100 points).