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

颗粒矿物学、边界层混合以及土壤粉尘气溶胶的气候响应

• 批准号: 0124258
• 负责人: Ron Miller
• 金额: $ 33.34万
• 依托单位: Columbia University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-12-15 至 2005-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0124258&HistoricalAwards=false
• 关键词: Particle; Mineralogy; Boundary; Layer; Mixing

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.

PIS将结合各种大气矿物的光学性质及其区域分布的最新汇编，以使尘埃的光学性质反映其来源区域的矿物学。它们将讨论以下问题：(1)尘埃羽流的成分如何沿着远离源区的轨迹变化，因为随着较大粒子的优先沉积，尘埃羽流的尺寸分布发生了变化？某些矿物的组成是否随着距离源头的距离而变得富含？(2)特定矿物，例如碳酸盐、伊利石和高岭石等粘土以及赤铁矿的大气浓度和沉积量的水平分布是什么？(3)如果考虑到源区的矿物学，尘埃气溶胶的辐射强迫和气候反应是什么？(4)将远行的撒哈拉沙尘的光学性质分配给每个源区域，在强迫和相关的气候反应方面造成了哪些区域误差？(V)将颗粒视为外部混合物的辐射效应是什么？为了解决这些问题，PIS将进行模拟，其中包括次网格尺度的地面风波动对尘埃排放的影响。这项工作很重要，因为它将加深我们对尘埃颗粒矿物学在气候中的作用的理解。