## Polar Products

Table 2.**_Cont._  
**Table 2.**_Cont._  
\begin{tabular}{p{113.8 pt} p{113.8 pt} p{113.8 pt}} \hline
**Product Name** & **Description** & **URL** \\ \hline Global Land Ice Measurements from Space (GLIMS) Glacier Database & The GLIMS project is a large, collaborative endeavor to digitize the world’s glaciers using satellite imagery. While the Randolph Glacier Inventory (see below) is a comprehensive snapshot, the GLIMS glacier database offers the ability to study change over time. Provided in multiple vector formats. & [[http://glims.org/](http://glims.org/)]([http://glims.org/](http://glims.org/)) [69] \\ \hline GlobICE & The GlobICE project provides measures of sea ice motion, deformation and flux through selected gateways for use in climate modeling and research. Products are derived from radar images taken by ESA’s ASAR Wide-Swath on-board ENVISAT and available from 2004 to 2011. The product is available for the Arctic and as a prototype for the Antarctic. & [[http://docs.google.com/file/d/0](http://docs.google.com/file/d/0)]([http://docs.google.com/file/d/0](http://docs.google.com/file/d/0)) \\ \hline Greenland Bed DEM & A bed elevation dataset for Greenland derived from a combination of multiple airborne ice thickness surveys undertaken between the 1970s and 2012, as well as satellite-derived elevations for non-glaciated terrain to produce a consistent surface over the entire island including across the glaciated-ice-free boundary. The DEM was extended to the continental margin with the aid of bathymetric data. The DEM is interpolated to 1-km postings; errors in bed elevation range from a minimum of \(\pm\)10 m to about \(\pm\)300 m, as a function of distance from an observation and local topographic variability. & [[https://docs.google.com/file/d/0](https://docs.google.com/file/d/0)]([https://docs.google.com/file/d/0](https://docs.google.com/file/d/0)) \\ \hline Greenland Ice Mapping Project (GIMP) DEM and ice mask & The GIMP DEM is constructed from a combination of ASTER and SPOT-5 DEM’s for the ice sheet periphery and margin (_i.e._, below the equilibrium line elevation) south of approximately 82.5\({}^{\circ}\)N and AVHRR photoclinometry in the ice sheet interior and far north. The DEM is posted to 30 m, although the “true” resolution of the DEM will vary from 40 m in areas of SPOT-5 coverage to 500 m in areas of photolcinometry. In addition, a raster binary land mask classification for Greenland’s ice area is available, mapped from Landsat and RADARSAT imagery. Both the DEM and the ice mask are on the same grid posting, broken into tiles across the continent; ice mask data are also available at 15-m posting. & [[http://nsidc.org/data/icebridge/](http://nsidc.org/data/icebridge/)]([http://nsidc.org/data/icebridge/](http://nsidc.org/data/icebridge/)) \\ \hline IceBridge & Products derived from aircraft missions using multiple instruments to map ice surface topography [127, 128, 129], bedrock topography beneath the ice sheets [136], ice and snow thickness [137] and sea ice distribution and freeboard [138]. Data from laser altimeters and radar sounders are paired with a gravimeter [139, 140], magnetometer [141], mapping camera [70] and other data to provide repeat measurements of rapidly-changing portions of land and sea ice. & [[http://nsidc.org/data/icebridge/](http://nsidc.org/data/icebridge/)]([http://nsidc.org/data/icebridge/](http://nsidc.org/data/icebridge/)) \\ \hline Icelandic Glacier DEMs & Airborne LiDAR DEMs were produced for over 90% of the ice-covered area of Iceland (including Vatnajokull, Hofsjokull, Myrdalsjodkull, Drangajokull, Eyjafallajokull and several smaller glaciers) as an International Polar Year deliverable. The DEMs also include a 500 m- to 1 km-wide buffer of progalcial geomorphological features. LiDAR point clouds were averaged and interpolated to produced DEMs gridded at 5-m postings; both the horizontal and vertical accuracy are under 0.5 m [114]. & Data are available on request from [PERSON] at the Icelandic Meteorological Office (tj)@vedur. **Table 2.**_Cont._