Analysis of rainwater in historical cities plays a key role to save ancient monuments from atmospheric agents. In this study we sampled the Rome’s rainwater from February to July of 2018 and we analysed them to determine their chemical and physical parameters: pH, redox potential, conductivity, temperature, and the concentration of the main inorganic ions (Na+, K+, Ca++, Mg++, F−, Cl−, NO3−, SO4−−). The volume of the daily fallen rainwater, the speed and direction of the wind in the sampling site were also collected. In order to find a correlation between all the above data we used the Principal Component Analysis (PCA). Results evidenced that there aren’t authentic “acid rains” as the minimum pH value that we found is 5.2. In some cases high concentrations of nitrates and sulphates were found with maximum values of 12.4 ppm and 18.7 ppm respectively. We also found no correlation between the rainwater’s composition and the seasonal period; on the contrary, the speed and direction of the wind, especially when coming from the sea or industrial country near Rome, play a noticeable role on the rainwater composition. Graphical abstract Graphical abstract

中文翻译：

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2018 年初罗马雨水的特征，旨在发现化学物理参数与污染源之间的相关性：一项统计研究

历史城市中的雨水分析对于从大气因素中拯救古代古迹起着关键作用。在这项研究中，我们对 2018 年 2 月至 7 月罗马的雨水进行了采样，并对其进行了分析，以确定它们的化学和物理参数：pH 值、氧化还原电位、电导率、温度以及主要无机离子（Na+、K+、Ca++、 Mg++、F-、Cl-、NO3-、SO4--)。还采集了采样点每日落下的雨水量、风速和风向。为了找到所有上述数据之间的相关性，我们使用了主成分分析 (PCA)。结果证明没有真正的“酸雨”，因为我们发现的最低 pH 值为 5.2。在某些情况下，发现了高浓度的硝酸盐和硫酸盐，最大值分别为 12.4 ppm 和 18。分别为 7 ppm。我们还发现雨水的成分与季节之间没有相关性；相反，风的速度和方向，尤其是来自罗马附近的海洋或工业国时，对雨水成分起着显着的作用。图形摘要图形摘要