日本地球惑星科学連合2018年大会

講演情報

[EE] 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-OS09] Marine ecosystems and biogeochemical cycles: theory, observation and modeling

2018年5月23日(水) 10:45 〜 12:15 105 (幕張メッセ国際会議場 1F)

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)、Eileen E Hofmann (共同)、Enrique N Curchitser (Rutgers University New Brunswick)、座長:平田 貴文(北海道大学)

11:45 〜 12:00

[AOS09-10] A one-dimensional turbulence-ecosystem model investigation of spring bloom initiation associated with mesoscale eddies

*Eligio de Raus Maure1Joji Ishizaka2Hidenori AIKI2Yoshihisa Mino2Hiroyuki Tomita2 (1.Graduate School of Envrionmental Studies, Nagoya University、2.Institute for Space-Earth Environmental Research, Nagoya University)

キーワード:modelling, mesoscale eddies, phytoplankton spring bloom

A lower trophic ecosystem model driven by a one-dimensional physical turbulence closure model was used to study phytoplankton dynamics and spring bloom initiation in mesoscale anticyclonic eddies (AEs) and cyclonic eddies (CEs), which are known to play an important role in the variability of ocean primary production and biogeochemical processes. The study is motivated by earlier work based on satellite data in which the timing of spring bloom initiation differed between AEs and CEs, and it was attributed to the difference in mixed-layer in eddies, shallower in CEs than in AEs. The nitrogen-phytoplankton-zooplankton-detritus (NPZD) model was used to simulate phytoplankton spring bloom associated with AEs and CEs. The physical model driving the biological one was forced by net heat flux, shortwave radiation and wind stress averaged within eddies. An initial annual integration was repeated for 4 years using annual composite (2002-2010) forcing in eddies in the Japan Sea. The last year of this integration was compared with satellite and in situ observations. The model was found to reproduce reasonably well the pattern of satellite and in situ chlorophyll a concentration associated with eddies. Based on these results, a new experiment was performed to investigate the spring bloom initiation following each eddy track. In the presentation, we expect to reveal the mechanism by which eddies influence the dynamics of phytoplankton spring blooms.