Mars Global Digital Dune Database (MGD3): north polar region (MC-1) distribution, applications, and volume estimates

The Mars Global Digital Dune Database (MGD(3)) now extends from 90 degrees N to 65 degrees S. The recently released north polar portion (MC-1) of MGD(3) adds similar to 844 000 km(2) of moderate-to large-size dark dunes to the previously released equatorial portion (MC-2 to MC-29) of the database. The database, available in GIS- and tabular-format in USGS Open-File Reports, makes it possible to examine global dune distribution patterns and to compare dunes with other global data sets (e.g. atmospheric models). MGD(3) can also be used by researchers to identify areas suitable for more focused studies. The utility of MGD(3) is demonstrated through three example applications. First, the uneven geographic distribution of the dunes is discussed and described. Second, dune-derived wind direction and its role as ground truth for atmospheric models is reviewed. Comparisons between dune-derived winds and global and mesoscale atmospheric models suggest that local topography may have an important influence on dune-forming winds. Third, the methods used here to estimate north polar dune volume are presented and these methods and estimates (1130 km(3) to 3250 km(3)) are compared with those of previous researchers (1158 km(3) to 15 000 km(3)). In the near future, MGD3 will be extended to include the south polar region. Published in 2011. This article is a US Government work and is in the public domain in the USA.