Mineral dust aerosols are a key component of the Earth system and a growing public health concern under climate change, as levels of dustiness increase. The Great Plains in the USA is particularly vulnerable to dust episodes, but land-atmosphere interactions contributing to large-scale dust transport are poorly constrained. This study compiled one of the longest quantitative, spatially-comprehensive records of dust events in the core Dust Bowl region never before available. Combined with experiment station reports from the Soil Conservation Service, reanalysis data products, and contemporary field surveys using a Portable In-Situ Wind Erosion Laboratory (PI-SWERL), the study examined meteorological catalysts for dust events and surficial dynamics of particle emission on the Southern High Plains (SHP). Multivariate statistical analyses of dust event variance yield 6 principal components capturing ˜60% of the variance of all dust event days. Results identified four dominant modes of dust events related to the season of occurrence and principal meteorological controls. A broader assessment of the potential emissivity of SHP soils reveals that disturbed surfaces begin to emit dust at a magnitude-higher rate than undisturbed surfaces as soon as the wind velocity reaches the threshold, increasing linearly with windspeed. Conversely, crusted undisturbed soil surfaces do not begin to reach the same flux rate until much higher windspeeds, at which point crusts are broken and emissivity rates increase exponentially. Significantly, the particle emissivity of undisturbed, loose sandy soils mirrors that of disturbed surfaces in relation to windspeed and potential magnitude of dust emission. This finding suggests that the prevalent sandier, rangeland soils of the SHP could be equal or greater dust sources than cultivated fields during periods of sustained, severe aridity.

随着粉尘含量的增加，矿物粉尘气溶胶是地球系统的关键组成部分，也是气候变化下公众日益关注的健康问题。美国的大平原特别容易受到沙尘暴的影响，但对大规模尘埃运输做出贡献的陆地-大气相互作用受到的约束却很少。这项研究汇编了迄今为止从未有过的最长的定量，空间综合性记录，该记录是核心“尘埃碗”区域中尘埃事件的记录。结合土壤保护局的实验站报告，再分析数据产品以及使用便携式原位风蚀实验室（PI-SWERL）进行的当代野外调查，该研究检查了气象催化剂的尘埃事件和地面上颗粒物排放的表面动力学。南部高原（SHP）。尘埃事件方差的多变量统计分析得出6个主要成分，捕获了所有尘埃事件天方差的〜60％。结果确定了与事件发生季节和主要气象控制有关的四种主要尘埃事件模式。对SHP土壤潜在发射率的更广泛评估显示，一旦风速达到阈值，受干扰的表面就会开始以比未受干扰的表面更高的速率发射尘埃，并随风速线性增加。相反，直到风速高得多时，结硬的原状土壤表面才开始达到相同的通量率，此时结壳破裂且发射率成倍增加。值得注意的是，粒子的发射率不受干扰，松散的沙土与风速和粉尘排放的潜在量有关，反映出受干扰的表面。这一发现表明，在持续，严重的干旱时期，小水电较普遍的沙质，牧场土壤可能比耕地具有更多或更多的粉尘源。