caa a22 4500 605455562 CHVBK 20210128100213.0 cr unu---uuuuu 210128e20151001xx s 000 0 eng 10.1007/s10872-015-0307-3 doi (NATIONALLICENCE)springer-10.1007/s10872-015-0307-3 Early summertime interannual variability in surface and subsurface temperature in the North Pacific [Elektronische Daten] [Shigeki Hosoda, Masami Nonaka, Yoshikazu Sasai, Hideharu Sasaki] Vertical structures of early summer ocean temperature variability on interannual and longer time scales in the North Pacific (NP) are investigated based on observational data obtained by the Argo. In the central and especially eastern NP regions, temperature variance is large but limited to the shallower layer. Given shallow mixed layer isolated by strong stratification from the subsurface layer due to strong short wave radiation in summer, the limitation to the shallower layer is expected. On the contrary, temperature variability in the western NP region frequently extends several hundred meters in depth. In the western NP, longer time scale variability of temperature is also apparent as temperature difference before and after 2008. Solutions of an eddy-resolving ocean general circulation model strongly suggest that the temperature variability is associated with changes in the oceanic frontal structures that extend to subsurface layer: enhancement of the northern branch of Kuroshio Extension and associated weakened meridional temperature gradients to the south and north of the current after 2008. The deep structure of temperature variability apparently indicates that it is caused not by atmospheric thermal forcing, but by oceanic structure changes, and it is corroborated by the similar variability in the subsurface salinity field. Also, it is shown that atmospheric thermal forcing strongly affects early summer sea surface temperature variability in the eastern NP, but not in the western NP. The Oceanographic Society of Japan and Springer Japan, 2015 Summertime temperature variability nationallicence North Pacific nationallicence Argo nationallicence OFES nationallicence Air-sea interaction nationallicence Interannual variability nationallicence Hosoda Shigeki Research and Develop Center for Global Change, Japan Agency for Marine-Earth Science and Technology, 2-15 Natsushima-cho, 237-0061, Yokosuka, Kanagawa, Japan aut Nonaka Masami Application Laboratory, Japan Agency for Marine-Earth Science and Technology, Yokohama, Kanagawa, Japan aut Sasai Yoshikazu Research and Develop Center for Global Change, Japan Agency for Marine-Earth Science and Technology, 2-15 Natsushima-cho, 237-0061, Yokosuka, Kanagawa, Japan aut Sasaki Hideharu Application Laboratory, Japan Agency for Marine-Earth Science and Technology, Yokohama, Kanagawa, Japan aut Journal of Oceanography Springer Japan 71/5(2015-10-01), 557-573 0916-8370 71:5<557 2015 71 10872 https://doi.org/10.1007/s10872-015-0307-3 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/s10872-015-0307-3 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Hosoda Shigeki Research and Develop Center for Global Change, Japan Agency for Marine-Earth Science and Technology, 2-15 Natsushima-cho, 237-0061, Yokosuka, Kanagawa, Japan aut NATIONALLICENCE 700 1- Nonaka Masami Application Laboratory, Japan Agency for Marine-Earth Science and Technology, Yokohama, Kanagawa, Japan aut NATIONALLICENCE 700 1- Sasai Yoshikazu Research and Develop Center for Global Change, Japan Agency for Marine-Earth Science and Technology, 2-15 Natsushima-cho, 237-0061, Yokosuka, Kanagawa, Japan aut NATIONALLICENCE 700 1- Sasaki Hideharu Application Laboratory, Japan Agency for Marine-Earth Science and Technology, Yokohama, Kanagawa, Japan aut NATIONALLICENCE 773 0- Journal of Oceanography Springer Japan 71/5(2015-10-01), 557-573 0916-8370 71:5<557 2015 71 10872