MIneral dust variability in the Southern Ocean (MISO)

在过去，极地冰芯是风尘颗粒沉积的唯一直接档案，矿物尘埃从沙漠地区长途运输到极地冰盖。虽然总粉尘沉降量是粉尘移动性的第一级衡量标准，因此粉尘源区的气候条件，颗粒大小分布允许对运输效率进行量化。在这里，我们将结合来自Dronning Maud Land的EPICA冰芯的最新南极尘埃记录，以及一个耦合的最先进的全球气候模式(ECHAM5)和隐式气溶胶计划(HAM)，以量化尘埃迁移、输送和沉积的古气候变化。高分辨率冰芯沙尘对大气沙尘浓度和粒度分布的分析将在全新世、MIS5.5和过渡到暖期期间与时间片模式运行并行进行。对于高度模拟的大气，适当的边界条件将仅从地球系统模式的长期模拟中进行模拟。作为回报，将评估沙尘对过去气候变化的影响。模式和冰芯数据处理的时间尺度从季节变化、年际变化到粉尘迁移和输送的长期变化，限制了潜在的尘埃源区及其时间变化，以及北极圈环流模式的时空变化。

Polar ice cores represent the only direct archive for the deposition of aeolian dust particles in the past, with mineral dust being transported over long-distances from desert regions to the polar ice sheets. While the total dust deposition is a first order measure of dust mobilization, hence climate conditions in the dust source regions, particle size distributions allow for a quantification of transport efficiency. Here we will combine latest Antarctic dust records from the EPICA ice core from Dronning Maud Land and a coupled state-of-the art Global Climate model (ECHAM5) with an implicit aerosol scheme (HAM) to quantify paleoclimatic changes in dust mobilization, transport and deposition. High-resolution ice core dust analysis on atmospheric dust concentration and particle size distribution will be performed for selected time slices in the Holocene, MIS 5.5 and during the transition into the warm periods in parallel to time slice model runs. Appropriate boundary conditions for the high simulation atmosphere only simulations will be taken from long simulations with an earth system model. In return the effect of dust on past climate changes will be assessed. The time scales addressed by both model and ice core data range from seasonal changes, interannual variability to long-term changes in dust mobilization and transport, constraining potential dust source regions and their temporal changes as well as spatiotemporal variability in Circumantarctic circulation patterns.