Transported Mineral Dust Deposition Case Study at a Hydrologically Sensitive Mountain Site: Size and Composition Shifts in Ambient Aerosol and Snowpack
Transported Mineral Dust Deposition Case Study at a Hydrologically Sensitive Mountain Site: Size and Composition Shifts in Ambient Aerosol and Snowpack
复制标题
水文敏感山区输送矿物粉尘沉积案例研究：环境气溶胶和积雪的尺寸和成分变化
DOI：
10.4209/aaqr.2015.05.0346
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发表时间：
2016
影响因子：
4
通讯作者：
A. Ault
中科院分区：
文献类型：
--
作者：
J. Axson;Hongru Shen;A. Bondy;C. Landry;J. Welz;J. Creamean;A. Ault
矿物粉尘在远山积雪中的沉积降低了积雪的反照率，增加了对太阳辐射的吸收，加速了积雪融化，改变了供水。矿物学和化学成分决定了粉尘颗粒的光学特性，这些特性随来源地区的不同而变化。虽然已经确定了偏远山区粉尘沉积的影响，但很少有研究将沉积事件期间环境颗粒的化学成分与沉积在积雪上的颗粒的性质联系起来。在科罗拉多州西南部的圣胡安山脉采集了环境颗粒和地表雪的样本，该山脉经常在春季经历尘埃沉积，并有证据表明尘埃促进了雪的融化。利用扫描电子显微镜和能量色散x射线能谱（SEM-EDX）对单个粒子进行分析。采用纳米粒子跟踪分析（NTA）技术测定了积雪表层不溶性残留物的数量、浓度和大小分布。在2015年4月2日至3日的一次小型沙尘事件中，大气气溶胶中富铁粉尘的吸收比例、雪中不溶性残留物的数量、浓度和大小均有所增加。这可以追溯到科罗拉多高原内矿物粉尘源区域的变化，在此期间，风速增加导致运输增加。输运尘埃的化学成分和矿物学变化有可能影响干沉积期间的积雪辐射强迫。此外，它还可以通过清除湿沉降过程中的颗粒来改变积雪，并改变云和地形降水的性质。了解这些影响对于了解偏远山区的水文循环至关重要。
Transported mineral dust deposition to remote mountain snow decreases snow albedo and increases absorption of solar radiation, which accelerates snowpack melt and alters water supply. Mineralogy and chemical composition determine dust particle optical properties, which vary by source region. While impacts of dust deposition at remote mountain sites have been established, few studies have connected the chemical composition of ambient particles during deposition events with the properties of those deposited on the snowpack. Ambient particles and surface snow were sampled in the San Juan Mountains of southwestern Colorado, which frequently experiences dust deposition in the spring and has evidence of dustenhanced snow melt. Individual particles were analyzed using scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX). The number concentration and size distribution of insoluble residues in the top level of snow were determined with nanoparticle tracking analysis (NTA). During a minor dust event (April 2-3, 2015), the fraction of absorbing iron-enriched dust in the ambient aerosol, the number concentration, and size of insoluble residues in snow all increased. This can be traced to shifts in mineral dust source region within the Colorado Plateau, during which, there were higher wind speeds leading to increased transport. The shift in chemical composition and mineralogy of the transported dust has the potential to impact snowpack radiative forcing during dry deposition. In addition, it can also modify the snowpack through scavenging of particles during wet deposition, as well as alter the properties of clouds and orographic precipitation. Understanding these impacts is crucial to understanding the hydrological cycle at remote mountain sites.
影响因子：
6.3
作者：
Carslaw, K. S.;Boucher, O.;Kulmala, M.
通讯作者：
Kulmala, M.