Chemical and meteorological influences on the lifetime of NO 3 at a semi-rural mountain site during PARADE
Chemical and meteorological influences on the lifetime of NO 3 at a semi-rural mountain site during PARADE
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DOI：
10.5194/acp-16-4867-2016
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发表时间：
2016-04
影响因子：
6.3
通讯作者：
N. Sobanski;Mingjin Tang;J. Thieser;G. Schuster;D. Pöhler;H. Fischer;W. Song;C. Sauvage;Jonathan Williams;J. Fachinger;F. Berkes;P. Hoor;U. Platt;J. Lelieveld;J. Crowley
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文献类型：
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作者：
N. Sobanski;Mingjin Tang;J. Thieser;G. Schuster;D. Pöhler;H. Fischer;W. Song;C. Sauvage;Jonathan Williams;J. Fachinger;F. Berkes;P. Hoor;U. Platt;J. Lelieveld;J. Crowley
抽象的。通过在德国陶努斯山脉的 PARADE 活动期间测量 NO2、O3 和 NO3（粒子和 RAdicals、Diel 对氧化机制的观察），我们得出了 NO3 和 N2O5 的夜间稳态寿命 (τss)。在某些夜晚，高 NO3 (∼ 200 pptv) 和 N2O5 (∼ 1 ppbv) 混合比与靠近地面的 τss 值相关，其中 NO3 超过 1 小时，N2O5 超过 3 小时。 NO3 和 N2O5 如此长的边界层寿命通常只在非常清洁/无反应的气团中遇到，而 PARADE 测量地点受到周围森林的生物排放和附近城市化/工业化中心的人为排放的影响。对几种与 NO3 发生反应的痕量气体的测量表明，推断的寿命明显长于根据总损失率计算的寿命。研究了 NO3 和 N2O5 寿命明显延长的几个潜在原因，包括形成 NO3 的其他途径和低洼残留层的存在。总体而言，异常寿命最可能的原因与气象条件有关，尽管 Criegee 中间体反应导致额外的 NO3 形成可能有所贡献。
Abstract. Through measurements of NO2, O3 and NO3 during the PARADE campaign (PArticles and RAdicals, Diel observations of mEchanisms of oxidation) in the German Taunus mountains we derive nighttime steady-state lifetimes (τss) of NO3 and N2O5. During some nights, high NO3 (∼ 200 pptv) and N2O5 (∼ 1 ppbv) mixing ratios were associated with values of τss that exceeded 1 h for NO3 and 3 h for N2O5 near the ground. Such long boundary-layer lifetimes for NO3 and N2O5 are usually only encountered in very clean/unreactive air masses, whereas the PARADE measurement site is impacted by both biogenic emissions from the surrounding forest and anthropogenic emissions from the nearby urbanised/industrialised centres. Measurement of several trace gases which are reactive towards NO3 indicates that the inferred lifetimes are significantly longer than those calculated from the summed loss rate. Several potential causes for the apparently extended NO3 and N2O5 lifetimes are examined, including additional routes to formation of NO3 and the presence of a low-lying residual layer. Overall, the most likely cause of the anomalous lifetimes are related to the meteorological conditions, though additional NO3 formation due to reactions of Criegee intermediates may contribute.