Particle Mineralogy, Boundary Layer Mixing, and the Climate Response to Soil Dust Aerosols

PI将结合联合收割机最近汇编的各种大气传播矿物的光学特性及其区域分布，以便尘埃光学特性反映其源区的矿物学。他们将讨论下列问题：（一）尘埃羽流的成分如何在其远离源区的轨迹上沿着变化，因为尺寸分布随着较大颗粒的优先沉积而变化？某些矿物质的含量是否随着距离矿源的距离而增加？(ii)特定矿物的大气浓度和沉积的水平分布是什么，例如，碳酸盐，粘土如伊利石和高岭石，以及赤铁矿？(iii)如果考虑源区的矿物学，沙尘气溶胶的辐射强迫和气候响应是什么？(iv)将遥远的撒哈拉沙漠尘埃的光学特性分配给每个源区，在强迫和相关的气候响应方面会产生什么样的区域误差？(v)把粒子看作外部混合物的辐射效应是什么？为了解决这些问题，PI将进行建模，其中包括次网格尺度的地面风波动对粉尘排放的影响。这项工作很重要，因为它将增强我们对尘埃颗粒矿物学对气候作用的理解。

The PIs will combine recent compilations of optical properties of various atmospheric-borne minerals and their regional distribution in order that dust optical properties reflect the mineralogy of their source region. They will address the following questions: (i) How does the composition of a dust plume vary along its trajectory away from the source region, as the size distribution changes with the preferential deposition of larger particles? Is the fraction of certain minerals enriched with distance from the source? (ii) What is the horizontal distribution of atmospheric concentration and deposition for particular minerals, e.g., carbonates, clays such as illite and kaolinite, and hematite? (iii) What is the radiative forcing by dust aerosols and the climate response if the mineralogy of the source region is accounted for? (iv) What regional errors in forcing and the associated climate response result from assigning optical properties of far-traveled Saharan dust to each source region? (v) What is the radiative effect of treating particles as external mixtures? To address these questions the PIs will undertake modeling that includes the effect of subgrid scale fluctuations of surface wind upon dust emission. The work is important because it will enhance our understanding of the role of dust particle mineralogy upon climate.