日本地球惑星科学連合2016年大会

講演情報

インターナショナルセッション(口頭発表)

セッション記号 A (大気水圏科学) » A-OS 海洋科学・海洋環境

[A-OS03] Marine ecosystem and biogeochemical cycles: theory, observation and modeling

2016年5月23日(月) 09:00 〜 10:30 202 (2F)

コンビーナ:*伊藤 進一(東京大学大気海洋研究所)、平田 貴文(北海道大学地球環境科学研究院)、Hofmann Eileen E.(Old Dominion University)、Charles Stock(Geophysical Fluid Dynamics Laboratory)、座長:平田 貴文(北海道大学地球環境科学研究院)

09:00 〜 09:15

[AOS03-01] Mixed Layer Controls on Ocean Carbon Cycling and Ocean Acidification

★招待講演

*Christopher L Sabine1Andrea Fassbender1,2,3Adrienne Sutton1,4Meghan F. Cronin1 (1.NOAA Pacific Marine Environmental Laboratory, 7600 Sand Point Way NE, Seattle WA 98115 USA、2.University Corporation for Atmospheric Research, Boulder, CO 80307 USA、3.School of Oceanography, University of Washington, Seattle WA 98115 USA、4.Joint Institute for the Study of the Ocean and Atmosphere, University of Washington, Seattle WA 98115 USA)

キーワード:carbon cycle, North Pacific, ocean acidification

The development of buoy-based autonomous carbon sensors has improved our ability to examine ocean carbon cycle dynamics and ocean acidification on time scales ranging from days to years. Processes contributing to mixed layer carbon inventory changes can be quantitatively assessed to understand the relative importance of physics, chemistry, and biology while helping us to better understand the magnitude of long-term change in the context of natural variability. Here we compare two North Pacific time series sites: The Kuroshio Extension Observatory (KEO) in the western subtropical North Pacific and Ocean Station Papa in the eastern subpolar North Pacific. Preliminary results at KEO indicate that 4.5 ± 2.2 mol C m-2 yr-1 is exported as organic carbon and 0.4 ± 1.1 mol C m-2 yr-1 is exported as calcium carbonate, with much of the export occurring during the spring bloom. At Papa, the organic and inorganic carbon exports are 2 ± 1 and 0.3 ± 0.3 mol C m-2 yr-1, respectively. Unlike KEO, export at Papa is spread out over the spring and summer months, then switches to net heterotrophy during the winter. Net organic carbon export at KEO is twice that of Papa, but the particulate inorganic carbon to particulate organic carbon ratio at Papa is about twice that of KEO. Observations suggest that both sites experience present day surface pH and Ωarag conditions outside the bounds of pre-industrial variability throughout the year.