The sixth release of the ArcticDEM initiative adds 32 percent more terrain data, mostly in Russia and Scandinavia. ArcticDEM provides a two-metre-resolution digital elevation model for arctic regions north of the 60th parallel, plus those bits of Alaska, Greenland and the Kamchatka Peninsula south of 60. The final product is due out next year. More at Earth & Space Science News. [GIS and Science]
A new digital elevation model of Alaska was released earlier this month. The result of a presidential directive to improve elevation maps of Alaska as a tool “to help to help communities understand and manage” the risks of climate change, the ArcticDEM project is a collaboration between the National Geospatial-Intelligence Agency (NGA), the National Science Foundation (NSF) and the University of Minnesota, among others. The unclassified data gives two-metre (or better) resolution across the state. Lower-resolution DEMs for the entire Arctic will follow next year.
Digital elevation data for Alaska had previously been poor; the National Geographic article leads with the point that Mars has better topographic maps than Alaska does. Most digital elevation data is collected by airplane—an impractical method in the far north; the ArcticDEM is based on stereo imagery from DigitalGlobe satellites. (As a comparison, the Shuttle Radar Topography Mission’s DEM resolution is 30 metres for the U.S., 90 metres elsewhere.)
After the cut, a comparison of digital elevation models pre- and post-ArcticDEM, using Anchorage, Alaska.
The first complete topographic map of Mercury, based on data from the MESSENGER mission, was released last Friday: MESSENGER, USGS. The version above is a Robinson projection without labels (Robinson with labels, global DEM). “Mercury’s surface is colored according the topography of the surface, with regions with higher elevations colored brown, yellow and red, and regions with lower elevations appearing blue and purple.” [GIS and Science, The National Map]