当前位置: X-MOL 学术ACS Earth Space Chem. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Understanding Sources of Atmospheric Hydrogen Chloride in Coastal Spring and Continental Winter
ACS Earth and Space Chemistry ( IF 3.4 ) Pub Date : 2021-08-18 , DOI: 10.1021/acsearthspacechem.1c00193
Andrea A. Angelucci 1 , Teles C. Furlani 1 , Xuan Wang 2 , Daniel J. Jacob 3, 4 , Trevor C. VandenBoer 1 , Cora J. Young 1
Affiliation  

Ambient 0.5 Hz hydrogen chloride (HCl) measurements were made in Canadian cities to investigate chlorine activation and constrain the tropospheric chlorine budget. Springtime HCl mixing ratios in a coastal city (St. John’s, NL) were up to 1200 parts per trillion by volume (pptv) with a median of 63 pptv and were consistently elevated during daytime. High time-resolution measurements allowed the attribution of events to general sources, including direct emissions. Most coastal HCl was related to sea-salt aerosol acid displacement (R1) and chlorine activation. Continental urban (Toronto, ON) wintertime HCl mixing ratios reached up to 541 and 172 pptv, with medians of 67 and 11 pptv during two sampling periods characterized by different wind directions. The absence of consistent relationships with NOx, temperature, and wind direction, as well as a lack of diurnal patterns, suggested uncharacterized direct sources of HCl. One period with road salting occurred during sampling, but no relationship to changes in HCl observations was found. The contribution of road salt to the measured HCl may have been masked by larger contributors (such as direct sources of HCl) or perhaps the relationship between HCl and road salt application is not immediate, and thus additional measurements over multiple salting events or between seasons would be required. GEOS-Chem modeled HCl temporal variations in mixing ratios agreed well with coastal measurements only. The measured mixing ratios were underestimated by the model in both locations, but to a greater degree (up to 3 orders of magnitude) in the continental city. The discrepancy between the model and measurements for the continental wintertime city emphasizes the need for a greater understanding of direct sources of HCl and the impact of road salt.

中文翻译:

了解沿海春季和大陆冬季大气氯化氢的来源

在加拿大城市进行了环境 0.5 Hz 氯化氢 (HCl) 测量,以研究氯活化和限制对流层氯预算。沿海城市(荷兰圣约翰斯)春季 HCl 混合比率高达 1200 万亿分之体积 (pptv),中值为 63 pptv,并且在白天持续升高。高时间分辨率测量允许将事件归因于一般来源,包括直接排放。大多数沿海 HCl 与海盐气溶胶酸置换 (R1) 和氯活化有关。大陆城市(多伦多,ON)冬季 HCl 混合比率达到 541 和 172 pptv,在以不同风向为特征的两个采样周期内,中值分别为 67 和 11 pptv。与 NO x缺乏一致的关系、温度和风向,以及缺乏昼夜模式,表明 HCl 的直接来源没有特征。采样期间发生了一段道路盐渍化,但未发现与 HCl 观测值变化的关系。路盐对测量的 HCl 的贡献可能被更大的贡献者(例如 HCl 的直接来源)所掩盖,或者 HCl 和路盐应用之间的关系可能不是直接的,因此在多个盐渍事件或季节之间进行额外测量会需要。GEOS-Chem 模拟的混合比的 HCl 时间变化仅与沿海测量结果一致。模型在两个地点都低估了测量的混合比,但在大陆城市中低估了更大的程度(高达 3 个数量级)。
更新日期:2021-09-16
down
wechat
bug