Phase Transitions of Aqueous Atmospheric Nitrate, Sulfate, and Ammonium Particles

该项目扩展了该研究员之前对粒子类别的气溶胶相行为研究，这些粒子类别对全球直接辐射强迫产生了重大的人为冷却贡献，旨在通过实验室和模拟相结合的方法定量评估对流层气溶胶相行为。将进行混合盐结晶实验，确定对流层相关模式粒子的结晶相对湿度，然后对相同成分的溶液进行光学常数测量。然后，这些数据将被纳入一个能够分辨辐射强迫和化学的全球化学输运模式。通过改进光学常数和对粒子相位的预测性理解，通过减少用于全球大气粒子评估的现有卫星反演算法中的不确定性，以及总体上增加目前对人为粒子如何促成辐射强迫的理解，这些结果将对社会产生广泛的科学影响。这些问题在能源规划、生产和使用、微粒污染的区域和远距离运输以及对全球气候的影响等方面对国际社会具有高度的政策相关性。该项目支持研究生和博士后研究人员的参与，并将研究成果整合到本科教育和推广中。

This project extends upon previous aerosol phase behavior studies by this investigator on particle classes exerting a significant anthropogenic cooling contribution to global direct radiative forcing, and is aimed at understanding tropospheric aerosol phase behavior assessed quantitatively through combined laboratory and modeling approaches. Mixed salt crystallization experiments will be conducted to determine crystallization relative humidity on relevant model tropospheric particles, followed by optical constant measurements on solutions with the same composition. These data will then be incorporated into a global chemical transport model capable of resolving radiative forcing and chemistry. Results will have a broad scientific impact on society through improved optical constants and predictive understanding of particle phase, by reducing uncertainties in existing satellite inversion algorithms used in the global assessment of atmospheric particles, and generally increasing current understanding of how anthropogenic particles contribute to radiative forcing. Such issues are of high policy relevance with respect to the global community in terms of energy planning, production and use, the regional and long-range transport of particulate pollution, and the impact on global climate. The project supports graduate student and postdoctoral researcher involvement, and includes integration of research results into undergraduate education and outreach.