Abstract The NH3(g) concentration measured at multi-site network in Kobe and Kitakyushu, Japan by using passive method continuously for one year in the late 2000s (September 2008–August 2009) and March 2018–February 2019, respectively, was statistically analyzed from the viewpoint of its controlling factors for temporal variation and spatial distribution. Nine survey sites were established in a region of Kobe, where highly urbanized, agricultural and mountainous areas were located within a 20-km x 20-km region; and one site in Kitakyushu, considered as urbanized and industrialized area, was taken into account. In terms of temporal variation, in both areas of Kobe and Kitakyushu, the NH3(g) concentration indicated lower level in the summer than those in other seasons and experienced higher concentration in colder period, which was newly found compared with the conventional wisdom and results in former studies. Regarding spatial distribution, the NH3(g) concentration showed large variations depending on the site, and the annual mean NH3(g) concentration ranged from 0 ppb (not detected: N.D.) to around 5 ppb. The NH3(g) concentration at the mountainous site with high elevation was the lowest, while it was the highest at the site where the contribution of agriculture was noticeably large in the NH3 inventory, followed by commercial and residential areas. The meteorological factors significantly contributed to the specific seasonal variation; moreover, multiple factors such as located situation, acid-base balance in the atmospheric reaction and vehicular emission were mutually related and presumably responsible for the seasonality of higher in the colder season and lower in the warmer season. When the NH3(g) concentration in the urbanized area is discussed, as in our present study area, the proportion of humans and pets (Human&Pet) to the total in the NH3 inventory could be a good parameter to account for the NH3(g) concentration.

中文翻译：

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日本市区大气氨浓度新发现的标志性季节变化

摘要 对2000年代后期（2008年9月-2009年8月）和2018年3月-2019年2月，采用被动法连续1年在日本神户和北九州多站点网络测得的NH3(g)浓度进行了统计分析。从其时空分布的控制因素来看。在神户地区建立了九个调查点，该地区高度城市化、农业和山区位于 20 公里 x 20 公里的区域内；北九州一处被认为是城市化和工业化区域的场地也被考虑在内。从时空变化来看，神户和北九州地区夏季NH3(g)浓度均低于其他季节，而在较冷时期浓度较高，这是新发现的与传统智慧相比的新发现，并在以前的研究中取得了成果。在空间分布方面，NH3(g)浓度因地点而异，年平均NH3(g)浓度范围从0 ppb（未检测到：ND）到5 ppb左右。NH3(g)浓度在高海拔山区最低，而在NH3清单中农业贡献显着大的场地最高，其次是商业和住宅区。气象因素对特定季节变化贡献显着；此外，所处位置等多种因素，大气反应中的酸碱平衡与车辆排放是相互关联的，可能是造成冷季高、暖季低的季节性原因。当讨论城市化地区的 NH3(g) 浓度时，如在我们目前的研究区域，人类和宠物 (Human&Pet) 在 NH3 库存中的比例可能是一个很好的参数来解释 NH3(g)专注。