geomorphometry.org

SRTM DEMs and ASTER GDEMs coupled with spatial statistical analysis offer a new perspective from which to investigate the synergies between desert landscapes, climate, and human impacts at a variety of scales. The derivation of geographic indices from these topographic models contributes to the global understanding of sand sea patterns, and how these patterns have self-organized and evolved through space and time. It is shown that the nearest neighbour distances between star dunes for the sand sea of the Al Liwa basin describe an evolutionary pathway between the compound mega-crescentic forms of the northern basin, and the simple and compound stellate forms of the more southern reaches. The measure of both local and global neighbour distances, as described by the R-statistic, is one of dune field maturity and directly relates to environmental circumstances, and climate change throughout the Quaternary. The signatures of landscape development described by geographic indices can be compared for all deserts, inclusive of planetary analogues such as Mars, which in turn, allows for planetary-scale processes to be better mapped, modeled and interpreted.