This shaded-relief image was created by J. Varner and E. Lim, CIRES, University of Colorado at Boulder. The image was created from ETOPO1 Ice Surface (cell-registered). The image was created with Generic Mapping Tools (GMT) [http://gmt.soest.hawaii.edu/] using three color palettes: blues for ocean depths and above sea-level lakes; greens and browns for dry land areas; and shades of white for the Antarctic and Greenland ice sheets and glaciers greater than 100 km2 using the GLIMS Glacier Database [http://nsidc.org/glims/] at the National Snow and Ice Data Center [http://nsidc.org/index.html]. More info on the development of ETOPO1 dataset can be found at http://www.ngdc.noaa.gov/mgg/global/relief/. The image was clipped at 35 degrees north and reprojected to a North Pole Lambert Azimuthal Equal Area projection by the Arctic Research Mapping Application (ARMAP) team [http://armap.org].