Spaced-OoooO-Out ::

It’s been a little while since my last global DEM news update but (somewhat belatedly) I came across Earth-Env DEM90 which merges SRTM (shuttle radar) and GDEM (ASTER photogrammetric) global DEMs. And more specifically the CGIAR-CSI SRTM DEM which is gap filled and hydrologically correct.

Neither DEM is actually completely global missing, to greater or lesser extents, the polar regions. GDEM has greater coverage (owing to the overpass of the satellite) but is generally considered to be less accurate than SRTM. So its inevitable that a merged product should arrive which covers ~91% of the globe and mitigates much of the noise and void problems of the individual products. Full methodology can be read here.