Atacama Desert Dust Emission Research (ADDER): Resolving aeolian dust source dynamics

阿塔卡马沙漠粉尘排放研究 (ADDER)：解决风沙源动态

• 批准号: NE/X002896/1
• 负责人: Joanna Nield
• 金额: $ 10.61万
• 依托单位: University of Southampton
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2022
• 资助国家: 英国
• 起止时间: 2022 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FX002896%2F1
• 关键词: Atacama; Desert; Dust; Emission; Research

Understanding when, where, and how windblown dust is emitted from deserts is important because dust can be detrimental to human health, can pollute downwind environmental systems, and, when airborne, can influence climate. Desert dust can also be rich in iron and other nutrients so when it falls into oceans downwind of its desert source, it can stimulate the productivity of marine biota in the surface waters. The impact of this is especially important in certain sensitive coastal areas where the mixing of cold water occurs close to the shore, such as at the Atacama and Namib Desert coastlines. These coastal waters can be particularly receptive to the nutrients that deposited dust might be providing.The UK Team have undertaken research on windblown dust in southern African deserts for many years. Our approach has been to use satellite observations to identify the sources of dust in different areas of the desert landscape, and then install state-of-the-art monitoring and survey equipment in these 'hot-spots' of dust emission to measure the wind and surface characteristics that control how and when dust is eroded by the wind. Our data have allowed improvements to be made in models of windblown dust emission into the atmosphere, and have also shown the significance of deposited dust in the fertilisation of the South Atlantic Ocean.The Atacama Desert is similar in many interesting respects to the Namib Desert in southern Africa. Both deserts are located on continental west coasts, fringed by cold ocean currents to the west and steep topography to the east. They have similar types of landscapes with a mix of dry river valleys, stony plains, and salty dry lakes. In the Namib, such surfaces have been shown to be prone to wind erosion and the generation of dust storms. However, whilst we know that winds generate dust in the Atacama Desert, we know very little about when and where such storms occur, or whether the dust contains iron which might affect the nutrient levels in the adjacent ocean waters. Our aim is to start a new collaboration of scientists from Chile, the UK, and Namibia to begin to answer these questions and determine the impacts of and controls on windblown dust in the Atacama Desert. We wish to achieve an understanding of the relevant processes in the Atacama which is as good as that which we have gained in the Namib.This research will bring together researchers from the UK and Namibia who have expertise in identifying sites of dust erosion (termed emission 'hot-spots') in Namibia, and a Chilean researcher who has expertise on the Atacama wind erosion system. Together this new team will establish, for the first time and at high resolution, where dust in the region comes from (using satellite images to identify 'hot-spots'), and how frequently dust storms occur. The team will then undertake fieldwork to explore the surface ground conditions at these 'hot-spots' and, at specific sites, install instruments to directly measure the amount of dust that is being eroded. Based on the outputs from this project, the team will develop a long-term collaborative relationship that will explore the effects of dust in the Atacama region in more detail through additional grant proposals. This will include investigating the influence of climate cycles on the efficiency of wind erosion, how important dust in this region is for ocean productivity, and the significance of human impact, such as mining, on generating windblown dust.

了解何时，何时和如何从沙漠中散发出尘埃很重要，因为灰尘可能不利于人类健康，可能会污染下风的环境系统，并且在空降时会影响气候。沙漠灰尘也可以富含铁和其他营养素，因此当它落入沙漠来源的海洋中时，它可以刺激地表水中海洋生物群的生产力。在某些敏感的沿海地区，冷水混合在海岸附近，例如Atacama和Namib沙漠海岸线，其影响尤其重要。这些沿海水域可能特别接受沉积灰尘可能提供的营养。我们的方法是使用卫星观测来确定沙漠景观不同区域中灰尘的来源，然后在这些“热点”中安装最先进的监测和测量设备，以测量控制风的风和表面特征，以控制灰尘如何被风侵蚀。我们的数据可以改善在大气中的风尘尘埃排放模型中，并且还显示了沉积灰尘在南大西洋的施肥中的重要性。在许多有趣的范围内，Atacama沙漠与南部非洲的纳米布沙漠相似。这两个沙漠都位于西部大陆海岸，西部的冷洋流边缘和东部的陡峭地形。它们具有类似类型的景观，以及干燥的河谷，石质平原和咸湖泊的混合物。在纳米布（Namib）中，此类表面已被证明容易发生风侵蚀和尘埃雨的产生。但是，尽管我们知道风在Atacama沙漠中产生灰尘，但我们对发生这种暴风雨的何时何地以及灰尘是否含有可能影响相邻海水中营养水平的铁知之甚少。我们的目的是启动来自智利，英国和纳米比亚的科学家的新合作，以开始回答这些问题，并确定Atacama沙漠中风尘的影响和控制的影响。我们希望了解Atacama中的相关过程与我们在纳米布（Namib）中获得的相关过程一样好。这项研究将使英国和纳米比亚的研究人员聚集在识别灰尘侵蚀地点（称为“被称为“热点””的尘埃场所）中的研究人员，以及在纳米比亚的智利研究人员，以及具有智商启发的智能研究员。这个新团队将共同建立该地区的灰尘来自（使用卫星图像来识别“热点”），以及发生沙尘暴的发生频率。然后，团队将进行现场工作，以探索这些“热点”的地面地面条件，并在特定地点安装工具以直接测量所侵蚀的灰尘量。根据该项目的产出，团队将建立长期的合作关系，该关系将通过其他赠款提案更详细地探索Atacama地区尘埃的影响。这将包括研究气候周期对风侵蚀效率的影响，该地区对海洋生产力的重要性以及人类影响的重要性，例如采矿，对产生风尘粉尘。