2017-09-20 4:07 GMT-05:00 Markus Metz <markus.metz.gisw...@gmail.com>: > > > On Tue, Sep 19, 2017 at 9:10 PM, Markus Metz <markus.metz.gisw...@gmail.com> > wrote: >> >> >> >> On Tue, Sep 19, 2017 at 5:53 PM, Laurent C. <lrn...@gmail.com> wrote: >> > >> > Hello Markus, >> > >> > Thanks for your interest. >> > By SRTM1 we mean the 1 arcsecond version of SRTM. As far as we know, it >> > comes in only one version. >> >> About USGS SRTM versions, see >> http://dx.doi.org/10.5067/MEaSUREs/SRTM/SRTMGL1.003 >> https://dds.cr.usgs.gov/srtm/What_are_these.pdf >> https://dds.cr.usgs.gov/srtm/version2_1/Documentation/SRTM_Topo.pdf >> >> the latter one states that "there is a difference between the data >> distributed via ftp from the Land Processes >> Distributed Active Archive Center [now https://dds.cr.usgs.gov/srtm/], and >> those available from the EROS Data Center" >> >> I am not sure if this still holds true. Following the EarthExplorer links >> https://lta.cr.usgs.gov/SRTMVF >> https://lta.cr.usgs.gov/SRTM1Arc >> >> it is not clear which versions these are. I guess the non-void filled >> version of the EarthExplorer is the subsampled version 2.1, the void filled >> version and the global 1 arc sec version are SRTM version 3. Just a guess, >> if in doubt, ask USGS. > > According to > https://lpdaac.usgs.gov/sites/default/files/public/measures/docs/NASA_SRTM_V3.pdf > and > https://lta.cr.usgs.gov/SRTM1Arc > > the USGS EarthExplorer most probably provides NGA version 2, not JPL/NASA > versions 2.1 or 3.
Markus, The JPL webpage about SRTM links to the USGS EROS website for download, which itself links to Earthexplorer: https://www2.jpl.nasa.gov/srtm/cbanddataproducts.html https://eros.usgs.gov/elevation-products Do you know if there is a more recent version of the 1 arcsec product, and where to find it? Best, Laurent > > Markus M >> >> > We could make it more clear during the revision. >> >> That would avoid confusion. For example, there is a 1 arc second version >> of version 2.1 ;-) >> >> Markus M >> >> > >> > Best, >> > Laurent >> > >> > On 19 Sep 2017 01:49, "Markus Metz" <markus.metz.gisw...@gmail.com> >> > wrote: >> > >> > >> > >> > On Tue, Sep 19, 2017 at 1:41 AM, Laurent C. <lrn...@gmail.com> wrote: >> > > >> > > Hello all, >> > > >> > > Open-access global DEMs like SRTM are a staple in our GIS community. >> > > Last year the JAXA released a new product, the ALOS World 3d 30m >> > > (AW3D30). >> > > Using GRASS and itzï we've carried out an assessment of AW3D30 from >> > > the point of view of flood modelling, and compared it to lidar, SRTM >> > > and ASTER. >> > >> > Very interesting study! I have a question about SRTM: in the paper you >> > write that you used SRTM version 1, but SRTM version 1 is practically not >> > used since version 2.1 has been made available. Since 2013, SRTM version 3 >> > has been available: >> > >> > http://dx.doi.org/10.5067/MEaSUREs/SRTM/SRTMGL1.003 >> > >> > SRTM version 3 is also the default for r.in.srtm.region. >> > >> > Best, >> > >> > Markus M >> > >> > > >> > > AW3D30 is indeed a very interesting product, and I thought that GRASS >> > > users could be interested in our results: >> > > https://doi.org/10.5281/zenodo.885571 >> > > >> > > Best regards, >> > > Laurent >> > > _______________________________________________ >> > > grass-user mailing list >> > > grass-user@lists.osgeo.org >> > > https://lists.osgeo.org/mailman/listinfo/grass-user >> > >> > > _______________________________________________ grass-user mailing list grass-user@lists.osgeo.org https://lists.osgeo.org/mailman/listinfo/grass-user