Biogeochemical cycle of particulate organic carbon in the Japan Sea and northwestern North Pacific

Otosaka, Shigeyoshi  ; Tanaka, Takayuki; Togawa, Orihiko ; Amano, Hikaru

An apparent age of particulate organic matter (POM) in seawater that is estimated from isotopic ratio of radiocarbon is convenient indicator for verifying transport processes of POM in the ocean. However, it is suggested that isotopic ratio of radiocarbon also reflects mixing of old POM from the surrounding regions and seafloor as well as an age of the POM. In this study, we discuss the cause of the variation in apparent age of POM from radiocarbon measurements of various particulate materials obtained at the northeastern Japan Sea and the northwestern North Pacific.