Wildfires emit mixtures of light‐absorbing aerosols (including black and brown carbon, BC and BrC, respectively) and more purely scattering organic aerosol (OA). BC, BrC, and OA interactions are complex and dynamic and evolve with aging in the atmosphere resulting in large uncertainties in their radiative forcing. We report microphysical, optical, and chemical measurements of multiple plumes from the Woodbury Fire (AZ, USA) observed at Los Alamos, NM, after 11–18 hr of atmospheric transit. This includes periods where the plumes exhibited little entrainment as well as periods that had become more dilute after mixing with background aerosol. Aerosol mass absorption cross sections (MAC) were enhanced by a factor of 1.5–2.2 greater than bare BC at 870 nm, suggesting lensing by nonabsorbing coatings following a core‐shell morphology. Larger MAC enhancement factors of 1.9–5.1 at 450 nm are greater than core‐shell morphology can explain and are attributed to BrC. MAC of OA (MAC_Org) at 450 nm was largest in intact portions of the plumes (peak value bounded between 0.6 and 0.9 m²/g [Org]) and decreased with plume dilution. We report a strong correlation between MAC_Org(450 nm) with the f_C2H4O2 (a tracer for levoglucosan‐like species) of coatings and of bulk OA indicating that BrC in the Woodbury Fire was coemitted with levoglucosan, a primary aerosol. f_C2H4O2 and MAC_Org(450 nm) are shown to vary between the edge and the core of plumes, demonstrating enhanced oxidation of OA and BrC bleaching near plume edges. Our process‐level finding can inform parameterizations of mixed BC, BrC, and OA properties for wildfire plumes in climate models.

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混合碳质气溶胶在2019年亚利桑那州伍德伯里火羽中增强吸收的光学和化学分析

野火散发出吸光气溶胶（分别包括黑碳和棕碳，BC和BrC）和更纯净的散射有机气溶胶（OA）的混合物。BC，BrC和OA相互作用是复杂而动态的，并且随着大气中的老化而发展，从而导致其辐射强迫的不确定性很大。我们报告了从大气中经过11-18小时后，在新墨西哥州的洛斯阿拉莫斯观察到的伍德伯里大火（美国亚利桑那州）的伍德伯里大火的多种物理，光学和化学测量。这包括羽流几乎没有夹带的时期，以及与背景气溶胶混合后变得更加稀薄的时期。气溶胶质量吸收横截面（MAC）比870 nm处的裸露BC增强1.5–2.2倍，这表明在遵循核-壳形态的情况下，通过不吸收涂层形成透镜。在450 nm处较大的MAC增强因子1.9–5.1大于核心-壳形态可以解释的原因，并归因于BrC。OA的MAC（MAC450 nm处的_Org）在羽状叶的完整部分最大（峰值介于0.6和0.9 m ² / g [Org]之间），并且随着羽状液稀释而降低。我们报告了MAC _Org（450 nm）与f _C2H4O2（左旋葡聚糖样物质的示踪剂）涂层和大量OA之间的密切相关性，表明在伍德伯里大火中的BrC与左旋葡聚糖（一种主要气溶胶）共存。f _C2H4O2和MAC _Org（450 nm）显示出在烟羽的边缘和核心之间变化，表明OA和BrC的氧化增强，并且烟羽边缘附近的BrC漂白。我们的过程级发现可以为气候模型中野火羽流的BC，BrC和OA混合属性参数化提供依据。