Reactive nitrogen (N_r: nitrate and ammonium) washout in Vienna (Austria) precipitation events were investigated in 2019. A total of 958 samples from 61 rain events representing >90 % of annual precipitation were collected at 5-30 min intervals for nitrate (NO₃^-) and ammonium (NH₄⁺) analyses and meteorological information. The data revealed systematic seasonal concentration variations for all N_r-species and a clear influence of rush-hour traffic on the kinetics of N-scavenging processes. The monthly nitrate and ammonium deposition was 0.69 ± 0.21 kg ha^-1 month^-1 and 1.02 ± 0.30 kg ha^-1 month^-1, respectively. Around 30 % of nitrate and 20 % of ammonium was dry deposition, and ∼30 % of each N-species was from distal sources associated with rainout processes. The half-life of below-cloud N-species were similar in the warmer seasons (1.7 ±0.2 h and 2.3±0.4 h for nitrate and ammonium). In winter, the ammonium half-life was significantly lower (1.4 h). N_r removal by wet-only in-cloud scavenging was slower than predicted by empirical models. HYSPLIT trajectory analysis revealed that N_r rainout from distal sources in spring had no prevailing direction, but higher N_r contributions were from N and W. In summer and winter, air masses from W, SW and SE were related to intense, medium, and low N_r contributions, respectively. The origin and path of these trajectories coincided with known NO_x hotspots in Europe.

对 2019 年维也纳（奥地利）降水事件中的活性氮（N _r：硝酸盐和铵）冲刷进行了调查。 以 5-30 分钟的间隔收集了来自 61 次降雨事件的 958 个样本，占年降水量的 90% 以上（ NO ₃ ^- ) 和铵 (NH ₄ ⁺ ) 分析和气象信息。数据揭示了所有 N _r物种的系统季节性浓度变化，以及高峰时段交通对 N 清除过程动力学的明显影响。每月的硝酸盐和铵沉积量为 0.69 ± 0.21 kg ha ^-1 month ^-1和 1.02 ± 0.30 kg ha ^-1 month ^-1， 分别。大约 30% 的硝酸盐和 20% 的铵盐是干沉降，每种 N 物种的约 30% 来自与降雨过程相关的远端来源。在温暖的季节，云下 N 物种的半衰期相似（硝酸盐和铵盐为 1.7 ± 0.2 小时和 2.3 ± 0.4 小时）。在冬季，铵的半衰期显着降低（1.4 小时）。仅湿式云中清除的N _r去除速度比经验模型预测的要慢。HYSPLIT轨迹分析表明，春季远端源的N _r降雨没有主导方向，但较高的N _r贡献来自N 和W。在夏季和冬季，来自W、SW 和SE 的气团与强、中、强相关。低 N _r贡献，分别。这些轨迹的起源和路径正好与已知的NO _X在欧洲的热点。