Agricultural harvesting emissions of ice-nucleating particles

作者：Kaitlyn J. Suski, Thomas C. J. Hill, Ezra J. T. Levin, Anna J. Miller, Paul J. DeMott, Sonia M. Kreidenweis · 发表于：Atmospheric chemistry and physics · 年份：2018 · DOI：10.5194/acp-18-13755-2018 · 被引用次数：134 · 研究领域：Atmospheric chemistry and aerosols、Atmospheric aerosols and clouds、Icing and De-icing Technologies

Abstract. Agricultural activities can modify natural ecosystems and change the nature of the aerosols emitted from those landscapes. The harvesting of crops can loft plant fragments and soil dust into the atmosphere that can travel long distances and interact with clouds far from their sources. In this way harvesting may contribute substantially to ice-nucleating particle (INP) concentrations, especially in regions where agriculture makes up a large percentage of land use. However, a full characterization of particles emitted during harvesting has not been reported. This study characterizes immersion mode INPs emitted during harvesting of several crops in the High Plains region of the United States. The Colorado State University Continuous Flow Diffusion Chamber (CFDC) and the Ice Spectrometer (IS) were utilized to measure INP concentrations during active harvesting of four crops in Kansas and Wyoming. Large spikes of INPs were observed during harvesting, with concentrations over 200 L−1 at −30 °C measured during a wheat harvest. To differentiate between mineral and organic components, a novel heating tube method was employed in real time upstream of the CFDC to deactivate organic INPs in situ. The results indicate that harvesting produces a complex mixture of organic, soil dust, and mineral components that varies for different crops. Electron microscopy analysis showed that while mineral components made up a large proportion of INPs, organic components comprised over 40 % of...