Development of a Dust-Iron Modeling System and a Benchmarking Regional Dust-Iron Budget Study

每年有大量的尘埃沉积到海洋中，相关的铁供应在海洋表面生物量生产中起着至关重要的作用，这决定了海洋从大气中吸收碳。然而，我们的定量估计的尘铁沉积到海洋中的不确定性困扰。我们非常依赖于尘埃模型来生成尘埃-铁沉积模式，以研究海洋生物群落对气候变化的响应，并估计二氧化碳浓度升高的大气中的海洋碳汇。现有的尘埃模型不能预测尘埃粒子的大小分布，这是必要的，以确定尘铁运输和沉积。在这个项目中，我们计划通过开发一个新的区域尘-铁模拟系统来解决研究尘-铁-碳关系中最关键的问题，该系统具有确定沙尘暴事件和零星弱沙尘事件的尺寸分辨尘-铁排放和沉积的能力。灰尘参数化的方法将是全新的。该模拟系统将被应用到澳大利亚的爱湖盆地，这是最大的风成尘铁源在南半球，并在尘铁观测和陆面特征丰富。如果成功，该项目将首次提供详细的区域铁预算，用于对全球尘铁模式和海洋生物群落对铁供应的反应进行基准模拟。

Large quantities of dust are deposited to the ocean each year and the associated iron supply plays an essential role in the surface-ocean biomass production which determines the ocean carbon uptake from the atmosphere. However, our quantitative estimates of dust-iron deposition to ocean are plagued with uncertainties. We very much rely on dust models to generate the dust-iron deposition patterns for studying the ocean biome response to climate change and to estimate the ocean carbon sink in an atmosphere with elevated CO2 concentration. Existing dust models cannot predict dust particles-size distributions which are necessary for determining dust-iron transport and deposition. In this project, we plan to tackle the most critical issues in studying the dust-iron-carbon relations by developing a new regional dust-iron modeling system with the capacity of determining size-resolved dust-iron emissions and depositions for both dust-storm events and sporadic weak dust events. The approach to dust parameterization will be completely new. The modeling system will be applied to the Lake Eyre Basin of Australia, which is the largest Aeolian dust-iron source in the southern Hemisphere and is rich in dust-iron observations and land-surface characterizations. If successful, this project will provide, for the first time, a detailed regional iron budget for benchmarking the simulations of global dust-iron patterns and ocean biome responses to iron supply.