A color shaded-relief image of Earth from ETOPO1 Ice Surface, created by NGDC (now NCEI). ETOPO1 is a 1 arc-minute global relief model of Earth's surface that integrates land topography and ocean bathymetry. It was built from numerous global and regional data sets, and is available in "Ice Surface" (top of Antarctic and Greenland ice sheets) and "Bedrock" (base of the ice sheets) versions. The image was created with Generic Mapping Tools (GMT) 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 other glaciers greater than 100 km2 using the GLIMS Glacier Database at the National Snow and Ice Data Center (NSIDC).