Dear GLIMS colleagues: I have good news about the coming GDEM3 and a "NASA DEM". Bob Crippen has done some magic and identified the pits and bump artifacts in the GDEMs versions 1, 2, and 3, and has found a way to replace most of them with real data, and identify those that still are erroneous and has masked them out and replaced with interpolation. The Antarctic and Greenland ice sheets will be mainly noise, as before, but most other parts of the world will be beautiful! The details I am sure will be presented when GDEM3 is released this summer and the "NASA DEM" is released near the end of 2017. It's the NASA DEM that most people will be using. For glaciological purposes, it remains limited by the fact that data spanning 2000 to 2014 are included, and one can never be sure what image dates were used for a given pixel in the GDEM. Anyway, it will be easier, less frustrating, and more accurate that previous GDEMs. Bon is saying that you will likely want to maintain GDEM3 as well as NASA DEM for a while until people discover the bugs. --Jeff Kargel