A study of the prediction method of the spatial distribution of ozone by kriging in Otsu city and its surrounding area

Abstract

In recent years, a simple and practical method for optimizing the existing air monitoring network in Japan is required because the photochemical oxidant pollution area is increasing. In this study, the spatial distribution of ozone and potential ozone (PO) were predicted by ordinary kriging based on the data from the monitoring network along with the data from passive samplers supplementing the network. Passive sampler data were confirmed to be equivalent to the monitoring data along with an adequate precision and trueness. Kriging was proved to be an effective method for the prediction of the spatial distribution of ozone and PO. The “Range”, which is obtained during the kriging process, represented the spatial scale and showed a positive correlation with the wind speed. However, in the case when the distribution was influenced by the relatively large air mass or by local emission sources, further analyses using a chemical transportation model or regression kriging with emission inventory as an auxiliary variable was considered to be necessary.