Abstract. The Global Monitoring Plan of the Minamata Convention on Mercury was established to generate long-term data necessary for evaluating the effectiveness of regulatory measures at a global scale. After 25 years monitoring (since 1995), Mace Head is one of the atmospheric monitoring stations with the longest mercury record, and has produced sufficient data for the analysis of temporal trends of Total Gaseous Mercury (TGM) in Europe and the Northern Atlantic. Using concentration-weighted trajectories for atmospheric mercury measured at Mace Head as well as other five locations in Europe, Amderma, Andøya, Villum, Waldhof and Zeppelin we identify the regional probabilistic source contribution factor and its changes for the period of 1996 to 2019. Temporal trends indicate that concentrations of mercury in the atmosphere in Europe and the Northern Atlantic have declined significantly over the past 25 years, at a non-monotonic rate averaging of 0.03 ng m^-3 year^-1. Concentrations of TGM at remote marine sites were shown to be affected by continental long-range transport, and evaluation of reanalysis back-trajectories display a significant decrease of TGM in continental air masses from Europe in the last two decades. In addition, using the relationship between mercury and other atmospheric trace gases that could serve as a source signature, we perform factorization regression analysis, based on positive rotatable factorization of non-singular matrix to solve probabilistic mass function. We reconstructed atmospheric mercury concentration and accessed the contribution of the major natural and anthropogenic sources. The positive matrix factorization (PMF) reveals that the downward trend is mainly associated with a factor with a high load of long-lived anthropogenic species.

中文翻译：

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欧洲和北大西洋上空大气汞的可能性和终点：25 年测量的时间趋势

摘要。《水俣公约》全球监测计划旨在生成评估全球监管措施有效性所需的长期数据。经过 25 年的监测（自 1995 年以来），Mace Head 是汞记录最长的大气监测站之一，并为分析欧洲和北大西洋总气态汞 (TGM) 的时间趋势提供了足够的数据。使用在 Mace Head 以及欧洲其他五个地点 Amderma、Andøya、Villum、Waldhof 和 Zeppelin 测量的大气汞浓度加权轨迹，我们确定了 1996 年至 2019 年期间的区域概率源贡献因子及其变化。^-3年^-1. 偏远海洋站点的 TGM 浓度被证明受大陆远程传输的影响，再分析回溯轨迹的评估显示，过去 20 年来自欧洲的大陆气团中的 TGM 显着下降。此外，利用汞与其他大气痕量气体之间的关系作为源特征，我们进行了分解回归分析，基于非奇异矩阵的正可旋转分解来求解概率质量函数。我们重建了大气汞浓度并获得了主要自然和人为来源的贡献。正矩阵分解（PMF）表明，下降趋势主要与长寿命人为物种负荷高的因素有关。