caa a22 4500 605455449 CHVBK 20210128100212.0 cr unu---uuuuu 210128e20150801xx s 000 0 eng 10.1007/s10872-015-0300-x doi (NATIONALLICENCE)springer-10.1007/s10872-015-0300-x Decadal variability of Subtropical Mode Water subduction and its impact on biogeochemistry [Elektronische Daten] [Eitarou Oka, Bo Qiu, Yusuke Takatani, Kazutaka Enyo, Daisuke Sasano, Naohiro Kosugi, Masao Ishii, Toshiya Nakano, Toshio Suga] Temperature and salinity data from Argo profiling floats during 2005-2014 were analyzed to examine the decadal variability of the North Pacific Subtropical Mode Water (STMW) in relation to that of the Kuroshio Extension (KE) system. The formation volume of STMW in the southern recirculation gyre of KE in the cooling season was larger during the stable KE period after 2010 than the unstable KE period of 2006-2009 by 50%. As a result, the volume and spatial extent of STMW increased (decreased) in the formation region during the stable (unstable) KE period, as well as in the southern, downstream region with a time lag of 1-2years. The decadal expansion and contraction of STMW were also detected by shipboard observations conducted routinely in the most downstream region near the western boundary, in terms of not only physical, but also biogeochemical parameters. After 2010, enhanced subduction of STMW consistently increased dissolved oxygen, pH, and aragonite saturation state and decreased potential vorticity, apparent oxygen utilization, nitrate, and dissolved inorganic carbon, among which changes of dissolved inorganic carbon, pH, and aragonite saturation state were against their long-term trends. These results indicate a new mechanism consisting of westward sea surface height anomaly propagation, the KE state transition, and the STMW formation and subduction, by which the climate variability affects physical and biogeochemical structures in the ocean's interior and potentially impacts the surface ocean acidification trend and biological production. The Oceanographic Society of Japan and Springer Japan, 2015 North Pacific Subtropical Mode Water nationallicence Subduction nationallicence Decadal variability nationallicence Kuroshio Extension nationallicence Biogeochemistry nationallicence Oka Eitarou Atmosphere and Ocean Research Institute, The University of Tokyo, 277-8564, Kashiwa, Japan aut Qiu Bo Department of Oceanography, University of Hawaii at Manoa, 96822, Honolulu, HI, USA aut Takatani Yusuke Global Environment and Marine Department, Japan Meteorological Agency, 100-8122, Tokyo, Japan aut Enyo Kazutaka Global Environment and Marine Department, Japan Meteorological Agency, 100-8122, Tokyo, Japan aut Sasano Daisuke Global Environment and Marine Department, Japan Meteorological Agency, 100-8122, Tokyo, Japan aut Kosugi Naohiro Oceanography and Geochemistry Research Department, Meteorological Research Institute, 305-0052, Tsukuba, Japan aut Ishii Masao Global Environment and Marine Department, Japan Meteorological Agency, 100-8122, Tokyo, Japan aut Nakano Toshiya Global Environment and Marine Department, Japan Meteorological Agency, 100-8122, Tokyo, Japan aut Suga Toshio Department of Geophysics, Graduate School of Science, Tohoku University, 980-8578, Sendai, Japan aut Journal of Oceanography Springer Japan 71/4(2015-08-01), 389-400 0916-8370 71:4<389 2015 71 10872 https://doi.org/10.1007/s10872-015-0300-x text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s10872-015-0300-x text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Oka Eitarou Atmosphere and Ocean Research Institute, The University of Tokyo, 277-8564, Kashiwa, Japan aut NATIONALLICENCE 700 1- Qiu Bo Department of Oceanography, University of Hawaii at Manoa, 96822, Honolulu, HI, USA aut NATIONALLICENCE 700 1- Takatani Yusuke Global Environment and Marine Department, Japan Meteorological Agency, 100-8122, Tokyo, Japan aut NATIONALLICENCE 700 1- Enyo Kazutaka Global Environment and Marine Department, Japan Meteorological Agency, 100-8122, Tokyo, Japan aut NATIONALLICENCE 700 1- Sasano Daisuke Global Environment and Marine Department, Japan Meteorological Agency, 100-8122, Tokyo, Japan aut NATIONALLICENCE 700 1- Kosugi Naohiro Oceanography and Geochemistry Research Department, Meteorological Research Institute, 305-0052, Tsukuba, Japan aut NATIONALLICENCE 700 1- Ishii Masao Global Environment and Marine Department, Japan Meteorological Agency, 100-8122, Tokyo, Japan aut NATIONALLICENCE 700 1- Nakano Toshiya Global Environment and Marine Department, Japan Meteorological Agency, 100-8122, Tokyo, Japan aut NATIONALLICENCE 700 1- Suga Toshio Department of Geophysics, Graduate School of Science, Tohoku University, 980-8578, Sendai, Japan aut NATIONALLICENCE 773 0- Journal of Oceanography Springer Japan 71/4(2015-08-01), 389-400 0916-8370 71:4<389 2015 71 10872