The Arctic Outflow Campaign: A Measurement Study to Characterize the Composition and Photochemistry of Arctic Air Transported Southward During Spring

9528031这个项目由多个调查员组成，研究春季北极空气流向北大西洋的情况。在冬季和春季，遥远的北极对流层中光化学活性污染物的水平会上升。最近的工作表明，通过北极的运输为北大西洋温带地区提供了大量总活性氮和非甲烷碳氢化合物。这一过程可能在该地区和其他偏远地区的对流层臭氧预算中发挥重要作用。由于缺乏对向南输送的北极空气中相关化合物的测量，目前对这些影响的了解受到限制。地面测量活动将于1996年1月至4月在纽芬兰的一个地点进行，地点在春季北极气流的主要通道内。测量将包括臭氧、一氧化氮、二氧化氮、过氧乙酸硝酸酐、过氧丙酸硝酸酐、烷基硝酸盐、总反应氮、非甲烷碳氢化合物、一氧化碳，以及标准气象参数和基于辐射计的二氧化氮光解速率。将使用实时等熵反向轨迹预报和气象分析来指导采样频率，以确保在外流事件期间有足够的覆盖率。反轨迹档案将有助于数据解释。这项研究的结果将被用来评估冬春北极水库对较低纬度地区NOx、NOY和非甲烷碳氢化合物的水平和形态的影响。将使用光化学箱模型估计对当地臭氧形成/破坏速度和预算的影响。

9528031 Honrath This project consists of a multi-investigator measurement campaign studying the springtime outflow of arctic air toward the North Atlantic. During winter and spring, levels of photochemically active pollutants are elevated in the remote arctic troposphere. Recent work indicates that transport through the Arctic provides a substantial flux of total reactive nitrogen (NOy) and non-methane hydrocarbons to the temperate North Atlantic region. This process may play a significant role in the tropospheric ozone budget of this and other remote regions. Current understanding of these effects is limited by an absence of measurements of the relevant compounds in southward-transported arctic air. The ground-based measurement campaign will take place during January-April, 1996, at a site in Newfoundland, within the dominant pathway of springtime arctic air flow. Measurements will include ozone, nitric oxide, nitrogen dioxide, peroxyacetic nitric anhydride, peroxypropionic nitric anhydride, alkyl nitrates, total reactive nitrogen, non-methane hydrocarbons, carbon monoxide, plus standard meteorological parameters and radiometer-based nitrogen dioxide photodissociation rates. Real-time isentropic back-trajectory forecasts and meteorological analyses will be used to guide the sampling frequency to ensure adequate coverage during outflow events. An archive of back-trajectories will assist in data interpretation. The results of this study will be used to assess the impact of the winter-spring arctic reservoir on the levels and speciation of NOx, NOy, and non-methane hydrocarbons at lower latitudes. Impacts on the local ozone formation/destruction rate and budget will be estimated using a photochemical box model.