Files for "Global Model Estimates of Atmospheric Al, Ca, Fe, Si, and Ti from Dust and Non-Dust Aerosols Informed by EMIT Surface Mineralogy and Evaluated Against Observations"

Datasets for "Global Model Estimates of Atmospheric Al, Ca, Fe, Si, and Ti from Dust and Non-Dust Aerosols Informed by EMIT Surface Mineralogy and Evaluated Against Observations" Atmospheric deposition of micro-nutrients like Fe has been shown to be important for ocean biogeochemistry. The largest source of atmospheric Fe and other elements (e.g., Ca, Al, Si, and Ti) is desert dust, although there are significant non-dust sources in some regions. However, past estimates of these elements have been substantially uncertain due to limited information about the composition of the desert source regions. Here we use elemental distributions estimated from new Earth Surface Mineral Dust Source Investigation (EMIT) observations, which provide mineralogical composition at the surface of the Earth based on imaging spectroscopy measurements from the International Space Station. We add in other sources of these elements (anthropogenic and natural) and compare to a compilation of available surface concentration data from stations over land and from shipborne observations. Our results suggest that the modeled distribution is similar to available observations, but discrepancies still exist in both natural desert dust regions as well as regions dominated by anthropogenic sources. Global budgets for the elements Ca, Al, Fe, Si, and Ti suggest that desert dust remains the dominant source for these elements but anthropogenic or volcanic sources are also important for these elements. Changes in elemental distributions since preindustrial times were also estimated.本数据集对应研究题为《基于地球表面矿物粉尘源调查（Earth Surface Mineral Dust Source Investigation，简称EMIT）的地表矿物学信息、并经观测数据对比验证的沙尘与非沙尘气溶胶中大气铝、钙、铁、硅及钛的全球模型估算》。 已有研究证实，铁等微量营养元素的大气沉降对海洋生物地球化学过程至关重要。 大气中铁及钙、铝、硅、钛等元素的最主要来源为沙漠沙尘，但部分区域亦存在不容忽视的非沙尘排放源。 然而，由于沙漠粉尘源区的组分信息较为匮乏，过往对上述元素的大气含量估算存在显著不确定性。 本研究采用基于全新地球表面矿物粉尘源调查（Earth Surface Mineral Dust Source Investigation，简称EMIT）观测数据反演得到的元素分布；该项目依托国际空间站的成像光谱测量技术，可获取全球地表的矿物组成信息。 本研究补充了上述元素的其他排放源（人为源与自然源），并将模型模拟结果与已公开的陆基观测站及船载观测得到的地表浓度数据集进行对比验证。 研究结果显示，模型模拟的元素分布与现有观测数据整体吻合，但在自然沙漠沙尘区及人为源主导区域仍存在一定偏差。 针对钙、铝、铁、硅及钛的全球收支分析表明，沙漠沙尘仍是上述元素的最主要来源，但人为源或火山源对上述元素的贡献同样不可忽视。 本研究同时估算了自工业化前期以来的元素分布变化情况。