Estimation of the origin of atmospheric methane by the use of atmospheric diffusion analysis and measurements of atmospheric radioactivity and isotope ratio.

对一种方法进行了测试，用于评估甲烷通量，通过比较空气中的甲烷浓度的测量值，从一个计算的扩散方程中进行了一次数字分析。“The Numeric value for the variation of radon concentration（雷达融合的变化）”，通过使用一个维度非稳定状态扩散当量来解释，可以证明radon concentration的临时变化：因此，扩散方程的数值解决方案的可靠性得到了证实，而且我们可以通过使用数值分析方法来确定甲烷通量，并在空气中记录甲烷和氡浓度的相似性的说明，一种方法是为了评估甲烷通量而开发的，它基于空气中雷达行为的知识。在名古屋市郊区的平均甲烷通量被发现了。在名古屋市南部-西部部分，区域甲烷通量increased in July and August and it amounted to 0.068 CH_4·m^<-2>·d^<-1>。根据对在Yatomi站点采样甲烷的碳同位素比率的分析，它揭示了几乎所有的甲烷都是从非化石来源提供的;它被认为是从帕迪字段起源的。一种评估瓦斯气非均匀通量的甲烷的方法是通过使用雷达和甲烷的日常变体的相似性提出的。年度流量的数量在爱知县为15.12 GgCH_4，在名古屋市为1.52 GgCH_4。

A Method was examined for evaluating methane flux by comparing measured value of methane concentration in air with calculated one from numerical analysis of a diffusion equation. The numerical values for the variation of radon concentration obtained by using one-dimensional non-steady state diffusion equation explain well the temporal variation of radon concentration : Thus the reliability of the numerical solution of the diffusion equation was revealed, and we can determine the methane flux by using the numerical analysis method.Taking notice of the similarity of the diurnal variation pattern of methane and radon concentrations in air, a method was developed for evaluating methane flux based on the knowledge of the behavior of radon in air. The averaged methane flux at the suburbs of Nagoya city area was obtained. At the south-west part of Nagoya city, regional methane flux increased in July and August and it amounted to 0.068 CH_4・m^<-2>・d^<-1>. According to the analysis of carbon isotope ratio of methane sampled at a site of Yatomi, it revealed that almost all of the methane are supplied from non-fossil origin ; It is considered to originate from paddy field.A method for evaluating vast aerial non-uniform flux of methane was proposed by using the similarity of the diurnal variations of radon and methane. The amount of annually flux was 15.12 GgCH_4 in Aichi prefecture and was 1.52 GgCH_4 in Nagoya city.