Download - GLIMS: Global Land Ice Measurements from Space

10CHAPTER 2. THE GLIMS - PROJECT AND RELEVANT GLACIER CHARACTERISTICS2.1.4 Transfer SpecicationsTo guarantee platform independence, the information from the regional centers andtheir glaciers have to be in ESRI shapele format.The ESRI shapele format is usedby multiple softwares (e.g. Open Source) in the GIS (Geographic Information System)based world. These glacier shapeles will then be sent to the NSIDC.Another advantage of the ESRI shapeles besides the platform independence is theminimisation of programming work and that later changes in the database can bemade easier.The transfer specications used in the GLIMS project are described in table 2.1.Shapele name Mandatory Type* Geometrysession.shp y 1,5,11,or 15 outline of region, or point in middleof region, or point where regionalcenter is locatedglaciers.shp y 1 or 11 point location of glaciersegments.shp y 3,5,13 or 15 line segmentsvec_sets.shp n 1,5,11 or 15 centre of mass (point)of vectorset, or convex hull around vectorsvec_points n 3 or 13 two - point vector arcshistograms.shp n 1 or 11 point at centre of glacierancillary.shp n 1 or 5images.shp y 5 polygon made of footprint, orpart of mosaic made up from thisimagepoint_meas.shp n 1 or 11 point measurementsTable 2.1: List of shapeles for GLIMS Data transfer. * shapele types. (afterhttp://www.glims.org)The session shapele contains information about the entire analysis session suchas the regional center ID, time of analysis completion, analyst's name, data sourceand description of processing.The glacier shapele holds the information of the individual glacier.In the segment shapele are the debris outlines, glacier outlines, rock outlines, centrelinesand also the position uncertainties.The image shapele contains information of the image used in the analysis.