Collaborative Research: NSFGEO-NERC: The Origin of Aeolian Dunes (TOAD)

风沙沙丘占据了地球表面的10%，无论是在广阔的沙漠沙海中，还是作为抵御沿海洪水的重要天然屏障。尽管对成熟沙丘进行了广泛的研究，但“被风吹过的沙丘是如何形成的？”这一问题仍未得到回答，但它是理解沙丘作为主要地质单位的核心，特别是考虑到沙丘在美国沙漠地区越来越多地出现，并对水和植被供应产生不利影响。这项研究将考察气流、表面特性、沙粒输送变化和河床形状之间的关键相互关系，这些关系有助于对新生沙丘是如何形成的有意义的理解。该项目将促进美国、英国和纳米比亚之间的国际合作。它将制作关于沙漠景观和地貌的公共教育材料，与美国和纳米比亚的国家公园建立伙伴关系，并为学生提供高质量的科学培训和实地经验。将在三个精心选择的已知沙丘开发地点进行高分辨率的地面属性和河床变化的实地监测。补充的实验室实验将能够准确地描述非常接近模拟沙丘表面的流动，这将与现场数据集一起驱动计算机模型，以测试在沙漠、海岸和其他行星上的一系列环境条件下，沙丘的启动和生长对不同控制措施的敏感性。总而言之，这种方法代表着一个机会，可以克服一个持久的高原，了解一个主要陆地地貌系统的起源。该小组将与美国大沙丘国家公园和纳米比亚纳米布-诺克卢夫特国家公园的工作人员合作，制作可广泛使用的公共参与材料。在纳米比亚戈巴贝布的一个专门的影响研讨会上，该小组将向感兴趣的纳米比亚当地和国际代表展示项目调查结果，以及如何利用这些调查结果影响社会和经济问题。该项目将吸引纳米比亚的本科生和研究生，并为他们提供宝贵的经验，这些经验可以激励他们在科学领域追求职业生涯。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Aeolian (wind-blown) sand dunes occupy 10% of the Earth's surface, both in vast desert sand seas and as important natural defenses against flooding along coasts. Despite extensive study of mature dunes, the question of "How do wind-blown dunes form?" remains unanswered, yet it is central to understanding dunes as major geological units, particularly given their increasing occurrence in desert regions of the United States and their adverse impact on water and vegetation supplies. This research will examine the key inter-relationships between airflow, surface properties, changes in sand transport and bedform shape that lie behind a meaningful understanding of how nascent dunes emerge. The project will promote international collaboration among the United States, the United Kingdom, and Namibia. It will generate public educational materials about desert landscapes and geomorphology, foster partnerships with National Parks in both the United States and Namibia, and provide quality scientific training and field experience to students.Field monitoring of surface properties and bedform change at high resolution will be performed at three carefully chosen locations of known dune development. Complementary laboratory experiments will enable accurate characterization of flow very close to the 3D surface of modelled dunes that, together with the field datasets, will drive a computer model to test the sensitivity of dune initiation and growth to different controls in a range of environmental conditions in deserts, coasts and on other planets. In concert, this approach represents an opportunity to overcome an enduring plateau for understanding the origins of one of the major terrestrial landform systems. The team will work with staff at Great Sand Dunes National Park in the United States and the Namib-Naukluft National Park in Namibia to create broadly accessible public engagement materials. At a dedicated impact workshop in Gobabeb, Namibia, the team will showcase to interested local Namibian and international delegates the project findings and how these findings could be used to influence societal and economic issues. The project will engage undergraduate and graduate students in Namibia and give them valuable experience that could inspire them to pursue careers in science.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.