Measurement of Tropospheric Nitric Acid and Aerosols

大气中由人为和自然过程产生的大部分氮氧化物转化为硝酸。硝酸最终通过湿法和干法沉积过程从大气中除去。气溶胶中硝酸和硝酸盐的这种表面损失是大气中氮氧化物的主要汇。硝酸不仅是大气氮循环中的重要物种，而且对降水的酸度也有重要贡献。了解对流层中硝酸的循环，特别是这种化合物从大气中去除的过程和速率，是当前大气化学中的一个关键问题。该项目旨在进一步了解通过土地、水和植物表面从大气中去除硝酸。抽样和分析程序已经发展到允许直接现场测量硝酸的干沉积。在这项研究的继续进行中，将在不同地点进行实地研究，以更好地确定硝酸的表面汇和这种化合物通过大陆或海洋大气的循环。

A majority of the oxides of nitrogen which are produced in the atmosphere by anthropogenic and natural processes is converted to nitric acid. Nitric acid is ultimately removed from the atmosphere by both wet and dry deposition processes. This surface loss of nitric acid and nitrate in aerosols is the major sink of the oxides of nitrogen in the atmosphere. Nitric acid is not only an important species in the atmospheric nitrogen cycle, but it can also contribute significantly to the acidity of precipitation. An understanding of the cycle of nitric acid in the troposphere, and especially the processes and rates of removal of this compounds from the atmosphere, is a current critical issue in atmospheric chemistry. This project is the continuation aimed at obtaining an improved understanding of the removal from the atmosphere of nitric acid by land, water and plant surfaces. Sampling and analytical procedures have been developed to permit direct field measurements of the dry deposition of nitric acid. In the continuation of this research, field studies will be performed at different locations to better define surface sinks of nitric acid and the cycle of this compound through the continental or marine atmosphere.