prtbckgnd.tif - Caribbean Regional Background Imagery for Puerto Rico Trench Featured Data
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Original 30 arc-second global topographic (GTOPO30) data accuracy varies by location because sources are chosen on the best available for the area, and use a total of eight sources worldwide. Sources could be raster or vector, with more accuracy claimed from the raster sources. The exact source(s) of the data for the extent shown in the Caribbean region were not determined. Horizontal accuracy is considered to be no greater than the spatial resolution of 1000 meters.
The second dataset is a compilation of bathymetric data provided by the British Oceanographic Data Centre in their General Bathymetric Chart of the Oceans (GEBCO) product. A wide variety of sources and scales were used by the data provider to digitize contours for use in the 1-minute grid product. Horizontal accuracy is considered to be no greater than the spatial resolution of 2000 meters. The graphical merging process, where GEBCO 1-minute data were combined with GTOPO30 topographic data, introduced additional error through exporting to a compressed JPEG image format. The JPEG format uses a lossy compression technique to reduce file size at the sacrifice of image quality.
Although all data and software published on this CD-ROM are used by the U.S. Geological Survey, no warranty, expressed or implied, is made by the U.S. Geological Survey as to the accuracy of the data and related materials and (or) the functioning of the software. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the U.S. Geological Survey in the use of these data, software, or related materials.