Atmospheric Chemistry

The summit of Mt. Fuji extends into the free troposphere, the atmosphere between an altitude of one kilometer aboveground and the stratosphere. In this layer, substances travel long distances without being subject to land surface frictions.
Since substances generated on the Eurasian Continent are carried from west to east by westerly winds generated in the mid-latitude of the northern hemisphere, Mt. Fuji, located at the eastern edge of the Eurasian Continent, is the optimum site for such observation.
With the current rapid economic growth in Asia, the importance of the observations and research at the Mt. Fuji station will increase as the station is located directly downwind of some of the largest combustion and other atmospheric effluents sources on the globe. 


Study on long-term CO2 observation at summit of Mt. Fuji

Hitoshi MUKAI
National Institute for Environmental Studies (NIES)

Center of Global Environmental Research (CGER)


Long term atmospheric CO2 concentration measurement at the summit of Mt. Fuji (3776m) has started by an automatic CO2 measurement system developed by National Institute for Environmental Studies (NIES) since August 2009. CO2 concentration at Mt. Fuji suggested back- ground concentration of middle tropospheric CO2 over East Asia.
In 2014, We continue the measurement and analysis of CO2 concentration and keep improving the long term measurement system. Moreover, We will start to measure CH4 concentration at summit of Mt. Fuji in this summer.


Long term observation of carbon monoxide, ozone, and sulfur dioxide during summer at the summit of Mt. Fuji

Shungo KATO

Faculty of Urban Environmental Sciences, Tokyo Metropolitan University


Carbon monoxide (CO), ozone (O3), sulfur dioxide (SO2) monitors are installed at the summit of Mt. Fuji and these concentrations are monitoring continuously. CO works as an indicator of atmospheric pollution. O3 works as an indicator of photochemical oxidation process of polluted air, and it makes actual bad influence to the atmosphere. SO2 is emitted from coal burning and eruption of volcano. These measurements have been conducted previous years, and comparison between different years, year to year variation can be performed.


Research on the long range transport and deposition amount of atmospheric mercury utilizing the mountain body of Mt. Fuji as a 4000m observation tower


The University of Shiga Prefecture


In this research, the following two subjects will be studied in order to elucidate the dynamics of atmospheric mercury and to evaluate its environmental effects, as well as to establish a numerical model to show and forecast the distribution pattern of mercury in the atmosphere.
1. Measurement and analysis of the transport of mercury in the free troposphere and boundary layer. 2. Evaluation of the chemical change of mercury during the long range transport. in addition, it is important to establish an simplified field determination method of mercury and other chemical species,which will serve as powerful tools to be utilized in the decision of emission regulation of mercury in 2013. (This project was stopped in 2015)


Measurements of aerosol particles and cloud condensation nuclei at the summit and a base of Mt. Fuji

Hiroshi OKOCHI

School of Science and Engineering, Waseda University

We will develop a newly continuous observational system of water-soluble gases and aerosols in the ambient and observe their concentrations at the summit of Mt. Fuji located in the free troposphere. The objectives are to elucidate background concentration levels of acidic gases, ammonia, and water-soluble components of aerosols in the free troposphere over Japan, to make clear the characteristics of background pollution in the air mass by the long-range transportation or upslope wind from the base of the mountain during the daytime in the summer, and to ascertain aerosol-cloud-precipitation interactions.


Study on the effect of aerosol particles on climate utilizing Mt. Fuji - Watching climate change by radon and ion concentrations -

Kazuhiko MIURA
Faculty of Science, Tokyo University of Science

Sulfur and organic species originated from ocean make new particles to increase the number of cloud condensation nuclei and change properties of cloud.  However, in the planetary boundary layer, there are many sea-salt particles that provide surfaces for heterogeneous chemical reactions with sulfur or organic gases. There are a few papers of new particle production observed in the boundary layer under a high-pressure system.  It suggests that particles are produced in the free atmosphere. As the summit of Mt. Fuji is usually positioned in the free troposphere, we can measure the variation of aerosol in the free troposphere. Our purpose is studying the relation between the new particle production process and other measuring elements.


Observation of chemical components in aerosols transported in the free troposphere and arriving at the summit of Mt. Fuji

Tokyo University of Agriculture and Technology

Fine particles transported in the free troposphere from East Asia will be observed at the summit of Mt. Fuji to elucidate the characteristics of the transport in the free troposphere. Size segregated collection of particles (PM10, PM2.5, PM1, PM0.5) will be carried out by use of a nano-sampler and chemical analyses of aerosols of each size range will be done. Samplings for each 12 hours in daytime and nighttime will be made to see the differences of air masses. (This project was stopped in 2012)


Observation of nitrogen oxides at the top of Mt. Fuji

Ryuichi Wada

Teikyo University of Science, Department of Natural and Environmental Science


The concentrations of nitrogen oxides (NO, and NO2) are determined continuously in summer using a chemiluminescence nitrogen oxides analyser which are installed in the observatory at the top of Mt. Fuji. Nitrogen oxides are important chemical species in the atmosphere, because they influence on the concentration of ozone. Nitrogen oxides are precursors of nitric acid, which causes acid rain. In this study, we will obtain the knowledge about across-boarder problems in East Asia.



Characterization of chemical components of PM2.5 long-range transported by simultaneous observation in China, South Korea and Japan

Shinichi YONEMOCHI/Center for environmental science in Saitama


Shiro Hatakeyama/Center for environmental science in Saitama


Yuichi Horii/Center for Environmental Science in Saitama


Hiroshi Okochi/Waseda university


Ki-ho Lee/Jeju National university, Korea

Chul-goo Hu/Jeju National University, Korea



Daily PM2.5 sampling is carried out using a sequential PM2.5 sampler at the summit of Mt.Fuji in order to clarify long-range transportation of PM2.5 in East Asia.  We conduct the sampling at 6 sites in China, South korea and Japan simultaneously, and measure chemical components of PM2.5 focusing on trace elements.


Furthermore, we compare chemical components of PM2.5 in atmosphere between free troposphere and above ground, and evaluate the influence of long-range transportation in summer.

Atmospheric aerosol observation with POPC network on mountain sites

Hiroshi Kobayashi/University of Yamanashi

Measurement of nanoparticles size distribution at summit of Mt. Fuji

Hidenori Higashi/Kanazawa University