Mixing of Asian mineral dust with anthropogenic pollutants allows pollutants (e.g. sulfate and nitrate) to be transported over longer distances (e.g. to the northern Pacific, even to North America) along with dust particles. This mixing therefore affects the atmospheric and oceanic environment at local, regional and even continental scales. In this study, we used a three-dimensional regional chemical transport model (Nested Air Quality Predicting Modeling System, NAQPMS) to examine the degree of mixing between Asian mineral dust and anthropogenic pollutants in a super-duststorm event during 19–22 March 2010. Influences of the mixing processes on regional atmospheric environmental and oceanic biogeochemical cycles were also investigated. A comparison with measurements showed that the model reproduced well the trajectory of long-range dust transport, the vertical dust profile, and the chemical evolution of dust particles. We found that along-path mixing processes during the long-range transport of Asian dust led to increasingly polluted particles. As a result, ~60% of the sulfate and 70–95% of the nitrate in the downwind regions was derived from active mixing processes of minerals with pollutants sourced from the North China Plain and enhanced by transport over South China. This mixing had a significant impact on the regional-scale atmospheric composition and oceanic biogeochemical cycle. Surface HNO3, SO2 and O3 were decreased by up to 90%, 40% and 30%, respectively, due to the heterogeneous reactions on dust particles. Fe solubility rose from ~0.5% in the Gobi region to ~3–5% in the northwestern Pacific, resulting from oxidization of SO2 on dust particles. Total Fe(II) deposition in the ocean region of East Asia reached 327 tons during the 4-day dust event, and created a calculated primary productivity of ~520 mgC m?2 d?1 in the Kuril Islands, which can support almost 100% of the observed mean marine primary productivity in spring in this region (526 mgC m?2 d?1).
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机译：亚洲矿物粉尘与人为污染物的混合使污染物（例如硫酸盐和硝酸盐）在较长的距离（例如，北太平洋，甚至到北美洲）以及粉尘颗粒上运输。因此，这种混合影响了当地，区域甚至大陆尺度的大气和海洋环境。在这项研究中，我们使用了一款三维区域化学传输模型（嵌套空气质量预测建模系统，NAQPMS），以研究2010年3月19日至22日的超级尘暴事件中亚洲矿物粉尘和人为污染物之间的混合程度。还研究了混合过程对区域大气环境和海洋生物地球化学循环的影响。与测量的比较表明，模型再现了远程灰尘传输，垂直粉尘剖面和粉尘颗粒的化学演变的轨迹。我们发现沿着亚洲粉尘的远程运输过程中的路径混合过程导致越来越污染的颗粒。结果，〜60％的硫酸盐和向下时断区域中的硝酸盐的硝酸盐源于矿物质的活性混合方法，其污染物来自华北平原，并通过南方运输增强。这种混合对区域规模的大气组成和海洋生物地球化学循环产生了重大影响。由于粉尘颗粒的非均相反应，表面HNO 3，SO2和O3分别降低至多90％，40％和30％。 Fe Solubility在戈壁地区的〜0.5％上升至西北太平洋的〜3-5％，由SO2氧化在尘埃粒子上。在4天的粉尘事件中，东亚海洋地区的Fe（II）沉积达到327吨，并在Kuril群岛中创造了〜520 MgC M？2 D？1的计算初级生产力，可以支持近100个观察到的平均海洋初级生产率的百分比在该区域中的春季（526mgcm≤2d≤1）。
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