Spaced Out ::

Another piece of news that slipped past the radar (O dear O dear….)…. JAXA is intending to produce another DEM, this time from ALOS PRISM data. ALOS (or Daichi) was launched in 2006 and then decommissioned (due to failure) in 2011 (see Wikipedia entry). Three instruments are on board ALOS: PRISM, PALSAR and AVNIR-2. PALSAR collects radar imagery, whilst AVNIR-2 is a multispectral radiometer with 10m spatial resolution. It is PRISM that is of particular interest as its design to collect stereo data for DEM production - it has three 2.5m resolution sensors (fore, aft and nadir) which collect stereo data.

The global mapping project aims to generate a 5m DEM of the world, with a secondary coarser resolution 30m DEM which will be free to use. There has been quite a lot written on using raw PRISM data (for example this paper; try Google Scholar) although it seems common to generate 10m pixels with an accuracy of 3-5m. Processing of the global DEM will take 2 years and my expectations are high that this will significantly boost detail of topographic features of the Earth’s surface.