HR: 0800h
AN: OS31A-0564    [Abstracts]
TI: Descriptions for CFCs distributions observed on the revisit of WHP A10
AU: * Sasaki, K
EM: ksasaki@jamstec.go.jp
AF: Japan Agency for Marine-Earth Science and Technology, 2-15, Natsushima, Yokosuka, 237-0061 Japan
AU: Watanabe, S
EM: swata@jamstec.go.jp
AF: Japan Agency for Marine-Earth Science and Technology, 2-15, Natsushima, Yokosuka, 237-0061 Japan
AU: Wakita, M
EM: mwakita@jamstec.go.jp
AF: Japan Agency for Marine-Earth Science and Technology, 2-15, Natsushima, Yokosuka, 237-0061 Japan
AU: Tanaka, S
EM: shinichi@ees.hokudai.ac.jp
AF: Graduate School of Environmental Earth Science, Hokkaido University, Kita 10, Nishi 5, Sapporo, 060-0810 Japan
AU: Sagishima, K
EM: ksagi@mwj.co.jp
AF: Geochemical Oceanography Section, Marine Works Japan Ltd, 2-16-32, Kamariyahigashi, Kanazawa-ku, Yokohama, 236-0042 Japan
AU: Yamamoto, H
EM: hideki@mwj.co.jp
AF: Geochemical Oceanography Section, Marine Works Japan Ltd, 2-16-32, Kamariyahigashi, Kanazawa-ku, Yokohama, 236-0042 Japan
AU: Fukasawa, M
EM: fksw@jamstec.go.jp
AF: Japan Agency for Marine-Earth Science and Technology, 2-15, Natsushima, Yokosuka, 237-0061 Japan
AB: Dissolved chlorofluorocarbons (here after CFCs) were measured along the WHP A10 in November 2003 by R/V Mirai cruise (MR03-K04 Leg 4). We describe the feature of these distributions and compare these in 1993 and in 2003. Maximum concentrations of CFC-11 and 12 were found around 300 - 400 m depth and were up to 3.7 pmol/kg and 1.8 pmol/kg, respectively. The maxima increase around 1.3 times of that of the previous results and deepen around 200 m deeper. These would reflect the increase in the mixing ratios of CFCs in the Atmosphere. However, the penetration depths of the CFCs were approximately 1500 m depth which is close to previous data. We detected the significant concentrations of CFCs in the deep water (below the 4000 db) at Hunter channel and at Cape Basin in our observation but could not found them in previous data. The concentrations were around 0.06 and 0.03 pmol/kg for CFC-11 and CFC-12, respectively. These mean the water that the age is younger than 1950s has reached these areas within recent 10 years.
DE: 4808 Chemical tracers
DE: 1724 Ocean sciences
SC: Ocean Sciences [OS]
MN: 2004 AGU Fall Meeting