For general global coverage ( specific locals may have elevation data art resolutions down to the centimeter level ) the GMTED2010 at https://topotools.cr.usgs.gov/gmted_viewer/viewer.htm
>From the Danielson, J.J., and Gesch, D.B., 2011, Global multi-resolution terrain elevation data 2010 (GMTED2010): U.S. Geological Survey Open-File Report 2011–1073 at https://pubs.usgs.gov/of/2011/1073/pdf/of2011-1073.pdf *"The USGS and the NGA have collaborated on the development of a notably enhanced global elevation model named the GMTED2010 that replaces GTOPO30 as the elevation dataset of choice for global and continental scale applications.The new model has been generated at three separate resolutions (horizontal post spacings) of 30 arc-seconds (about1 kilometer), 15 arc-seconds (about 500 meters), and 7.5 arc-seconds (about 250 meters)."* I prefer it because it is one of the few non-commercial extant elevation sources that has extensive technical documentation on what it was derived from, how it was processed, and the quality level in any particular region ( see the overview report linked above ). In the United States, the 3D Elevation Program (3DEP) is the best nation-wide available ( https://www.usgs.gov/core-science-systems/ngp/3dep ). It also has a clear intellectual property trail if you are publishing or re-distributing your data products downstream. Of course, specific counties, provinces, municipalities, and agency projects may have far more up to date and higher resolution elevation data. Michael Patrick
_______________________________________________ Gvsig_internacional mailing list Gvsig_internacional@listserv.gva.es To see the archives, edit your preferences or unsubscribe from this mailing list, please access this url: https://listserv.gva.es/cgi-bin/mailman/listinfo/gvsig_internacional