Continuous Observational Data of Atmospheric CO2 Mixing Ratios on Hateruma Island

The present data set is a set of continuous observational data of background CO2 mixing ratios in the vicinity of 20°N in the Western Pacific Ocean facing East Asia, measured on Hateruma Island, Okinawa Prefecture, Japan. Hateruma Island is a small island with a diameter of approx. 5 km. Because it is subjected to very small influence from local terrestrial ecosystem and/or anthropogenic CO2 emissions, the daily variations are small and the CO2 mixing ratios observed here can therefore be regarded as representative of the sub-tropics in the East Asian region. The Hateruma data reflects the influence from the Pacific Ocean in summer and from the Asian continent in winter, located downwind from each region, respectively.

本数据集为日本冲绳县波照间岛（Hateruma Island）所测得的西太平洋东亚毗邻海域北纬20°附近区域背景大气二氧化碳（CO₂）混合比连续观测数据。波照间岛为直径约5公里的小型岛屿，受当地陆地生态系统及人为二氧化碳排放的影响极微，因此其观测到的二氧化碳混合比日变化幅度极小，该站点的观测数据可视为东亚副热带区域背景大气二氧化碳的代表性数据集。由于该站点分别处于太平洋与亚洲大陆的下风地带，因此波照间岛的观测数据在夏季可反映太平洋海域的大气特征，冬季则体现亚洲大陆的大气影响。