How to show depths of GEBCO Grided Data

muhammadtalib

GEBCO’s global grids are terrain models for ocean and land with a spatial resolution of 15 arc seconds. The data values are pixel-centre registered i.e. they refer to elevations, in meters, at the centre of grid cells. The SRTM15+ base grid has been augmented with the gridded bathymetric data sets. I downloaded these Datasets in Tiff format, when load it in Global Mapper, How can i Display bathymetric data means Depths data in meters