Wind systems and dune formation in Gale Crater, Mars

该项目的目的是模拟火星盖尔陨石坑沙丘系统的形态动力学。对主要发生在陨石坑内部的火星沙丘的成因和动力学的定量了解，对于正确重建火星的地质历史和这颗红色星球上的气候演变具有重要意义。然而，火星上的火山口内沙丘过程主要受地形对当地输送条件的影响，这在火星环流模型中是无法解决的。为了定量描述这种影响，在本项目中，一个精确描述陆地沙丘形状和动力学的地形动力学沙丘模型将被扩展，以将火星表面的数字高程模型纳入到湍流地面风场和连接的沙通量的计算中。基于对当地风向和沙丘形态的数值预报，将计算盖尔陨石坑不同沙丘场的沙玫瑰。此外，这些结果还将被用于研究盖尔陨石坑沙丘区不同沙丘形态的稳定性。之后，该模型将被应用于盖尔陨石坑沙丘沙源的调查。该模型将有助于研究火星上的区域风向和风沙沉积的来源。

The aim of this project is to model the morphodynamics of the dune systems in Gale Crater, Mars. The quantitative understanding of the genesis and dynamics of Mars dunes - which occur mainly in the interior of craters - has implications to correctly reconstruct the geologic history of Mars and the evolution of the climate on the red planet. However, intra-crater dune processes on Mars are mainly controlled by topographic effects on local transport conditions, which cannot be resolved in Mars Circulation Models. To quantitatively describe such effects, in the present project a morphodynamic dune model, which accurately describes the shape and dynamics of terrestrial dunes, will be extended to incorporate the digital elevation model of the Martian surface into the calculation of the turbulent surface wind field and the concatenated sand flux. Based on numerical predictions of local wind directions and dune morphology, the sand roses of the different dune fields in Gale Crater will be calculated. Moreover, these results will be used to investigate the stability of the different dune morphologies in Gale Crater dune fields. Thereafter, the model will be applied to investigate the sources of dune sand in Gale Crater. The model will contribute to the investigation of regional wind regimes and the origins of aeolian sediments on Mars.