Collaborative Research: Gas, Cloudwater, and Rain Hydrogen Peroxide and Methylhydroperoxide Measurements in RICO (Rain in Cumulus Over the Ocean)

调查人员将对“海洋积云降雨”实验作出贡献，方法是测量一架研究飞机C-130在安提瓜附近飞行期间所研究的云层内部和附近的过氧化氢和甲基氢过氧化物的浓度。结合其他测量，测量的浓度将表明云的年龄和夹带到云中的环境空气的量。更广泛的RICO实验旨在研究暖雨形成的机制，因此云龄的指示可以通过指示雨形成的时间来为更广泛的实验目标做出重大贡献。该研究还将描述云滴中发生的氧化作用，并调查是否会因此产生大量可溶性物质，导致液滴蒸发后留下的残留物作为云凝结核比液滴形成的原始核更活跃。此外，由于降水的影响，这两种过氧化物在垂直方向上的分布不同，因此它们的比例可以确定受降水影响的地块。这些研究都将有助于更好地了解降水过程和信风积云的特征，这项工作也将对培养研究生和本科生作出重要贡献，从而有助于发展未来的大气化学研究能力。所开发的技术如果成功，将成为未来云研究的重要组成部分。通过提高对氧化如何有助于云凝结核的生长和改变的理解，该项目有可能帮助更好地了解控制云微观结构的化学过程，从而了解云与气候系统的相互作用。

The investigators will contribute to the "Rain in Cumulus over the Ocean" (RICO) experiment by measuring the concentration of hydrogen peroxide and methylhydroperoxide inside and in the vicinity of clouds studied by a research aircraft, the C-130, during flights near Antigua. In combination with other measurements, the measured concentrations will indicate cloud age and the amount of environmental air entrained into the clouds. The broader RICO experiment seeks to study the mechanisms of warm-rain formation, so indications of cloud age can make substantial contributions to the broader experimental objectives by indicating the time available for formation of rain. The study will also characterize the oxidization that occurs in cloud droplets and investigate if substantial production of soluble material occurs as a consequence, causing the residue left upon evaporation of a droplet to be substantially more active as a cloud condensation nucleus than was the original nucleus on which the droplet formed. Furthermore, the two peroxide species are distributed differently in the vertical as a result of precipitation, so their ratio can identify parcels that have been affected by precipitation. These studies will all contribute to better understanding of precipitation processes and the characteristics of trade wind Cumulus clouds.The work will also make important contributions to the training of graduate and undergraduate students and so help develop future capabilities for research in atmospheric chemistry. The techniques to be developed, if shown to be successful, could become important components of future cloud studies. By improving understanding of how oxidation contributes to the growth and modification of cloud condensation nuclei, the project has the potential to help develop a better understanding of the chemical processes that control the microstructure of clouds and hence the interactions of clouds with the climate system.