The Hateruma Global Environment Monitoring Station is located at the southern end of Japan. The station was established in 1992 to monitor the long-term trends of greenhouse gases (GHGs) in Eastern Asia.
Hateruma Island, a small sub-tropical island and part of the Sakishima Islands, is located at more than 1000 km from mainland Japan. The wind is northerly to northeasterly in autumn-winter and southerly to southeasterly in spring-summer. The annual mean wind speed at the top of the tower (46.5 m above sea level) is about 8 m/s. The surface temperature is about 24ºC and the annual rainfall is about 1900 mm. Hourly measurements of halocarbons have been performed at Hateruma since 2004. A fully automated preconcentration/gas chromatograph/mass spectrometer system measures ~50 trace gases, including halocarbons.