日本地球惑星科学連合2019年大会

講演情報

[E] ポスター発表

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-OS12] Marine ecosystems and biogeochemical cycles: theory, observation and modeling

2019年5月27日(月) 17:15 〜 18:30 ポスター会場 (幕張メッセ国際展示場 8ホール)

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)、Enrique N Curchitser(Rutgers University New Brunswick)、Eileen E Hofmann(Old Dominion University)

[AOS12-P04] The global oceanic iron distribution estimated by data assimilation approach

*土居 知将1長船 哲史1増田 周平1小畑 元2三角 和弘3西岡 純4 (1.海洋研究開発機構、2.東京大学、3.電力中央研究所、4.北海道大学)

キーワード:海洋溶存鉄、データ同化

Since distribution of oceanic iron is considered as one of the restriction factors of phytoplankton activity, it is necessary for a pelagic lower trophic level ecosystem model to take into account the effect of iron. In this study, we constructed a three dimensional gridded data of oceanic iron concentration by using both available in situ observation and simple iron cycle model. For the physical process of iron transport, the advection/diffusion model was used along with the flow field of ESTOC (Estimated State of Global Ocean for Climate Research). The falling atmospheric dust in the sea-surface and flux from the sediment at sea floor of the coast were set as the input of the iron. The scavenging or desorption by particulate matter in the water column were employed as the control variables and we constructed the simple iron cycle model. The optimized set of control parameters was obtained based on a Green's function approach by using available in situ iron concentration observations. The results showed that the iron concentration in the southern hemisphere is lower than northern hemisphere, and the low iron regions were well reproduced around the regions of high nutrient / low chlorophyll. Moreover, it is suggested that the Atlantic Ocean is more affected by the atmospheric dust compared with the Pacific Ocean.