Characterization of the Atmospheric Concentration and Air-Snow Exchange of Soluble Gaseous Acids at Summit, Greenland

该奖项是为了支持一个为期两年的项目，该项目旨在研究格陵兰Summit的大气和地表雪中硝酸盐的来源。未经资助的试点研究的初步结果表明，硝酸（HNO3）不是唯一的，甚至可能不是山顶夏季积雪中硝酸盐（NO3-）的主要氮种。过氧硝酸乙酰基和一种或多种硝酸烷基似乎是最有可能的候选物质，它们也可能是峰顶雪表面上观察到的有机酸浓度升高的原因。1995年和1996年两季将在首脑会议的不同高度用2个雾室取样器对可溶性酸性气体进行梯度测量。这些测量将辅以密集的实验，将雾室样品与尼龙过滤器样品进行比较，并在雾室入口使用尼龙过滤器，以量化除硝酸外的可溶性氮种类。这项研究的主要目标将是改进对极地冰中硝酸盐记录的解释，但也期望对冰雪覆盖表面的活性氮化学有更多的了解。

This award is for support for a two year program to study the origin of nitrate in the atmosphere and surface snow at Summit, Greenland. Preliminary results from unfunded pilot studies suggest that nitric acid (HNO3) is not the only, and may not even be the major nitrogen species contributing to nitrate (NO3-) in summer-time snow at Summit. Peroxy acetyl nitrate and one or more alkyl nitrate species seem to be the most likely candidates, and they may also be contributing to the elevated concentrations of organic acids observed just above the snow surface at Summit. Gradient measurements of soluble acidic gases will be made with 2 mist chamber samplers at different heights in the 1995 and 1996 seasons at Summit. These measurements will be complemented with intensive experiments comparing mist chamber samples to nylon filter samples and the use of nylon filters on the mist chamber inlet, to quantify soluble nitrogen species besides nitric acid. The primary goal of this study will be to enable improved interpretation of the nitrate records in polar ice, but additional insights into reactive nitrogen chemistry over snow covered surfaces are also anticipated.