Influence of the Atmospheric Aerosol of Snowfall Scavenging Efficiencies and Precipitation Rates.

在科罗拉多州西北部的一个山顶地点，对气溶胶清除、降水率和效率的研究将继续进行。将分析云中气溶胶粒子、云滴和冰粒作为大小函数的测量结果，以及先前制作的云凝结核（CCN）光谱，以确定降水云的三种水成分（冰、水和蒸汽）中化学物质的分布。根据这些测量，将评估不同数量的自然和人为气溶胶颗粒对气溶胶颗粒清除和降水过程的影响。由于主要大气气溶胶CCN颗粒源（自然与人为）的变化，云滴大小分布的变化将与两个主要的冰粒生长过程有关：液滴的增加与水蒸气的扩散。云内气溶胶和水团去除机制和速率的这些变化将用于确定大气气溶胶浓度的变化如何影响云微观结构、污染物清除和降雪率。

Studies of aerosol scavenging and precipitation rates and efficiencies in snowing clouds at a mountaintop site in northwestern Colorado will continue. In-cloud measurements of aerosol particles, cloud droplets and ice particles as a function of size, and cloud condensation nuclei (CCN) spectra previously made will be analyzed to determine the distribution of chemical species among the three water components of a precipitating cloud: ice, water and vapor. From these measurements, the effect of varying populations of natural and anthropogenic aerosol particles on aerosol particle scavenging and precipitation processes will be assessed. Variations in the cloud droplet size distribution as a result of changes in the dominant atmospheric aerosol CCN particle source (natural versus anthropogenic) will be related to the two primary ice particle growth processes: accretion of droplets versus diffusion of water vapor. These variations in the in-cloud aerosol and water mass removal mechanisms and rates will be used to determine how changes in atmospheric aerosol concentrations effect cloud microstructure, pollutant scavenging and snowfall rates.