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) 15:30 〜 17:00 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-P07] A key spot and timing to monitor chlorophyll-a in the Kuroshio western boundary current

*平田 貴文1 (1.北海道大学地球環境科学研究院)

キーワード:黒潮、クロロフィル、リモートセンシング

The Kuroshio western boundary current originates from the subtropics in the Western Pacific and carries a thermal energy and oceanic water mass towards the north, including the south coasts and offshore islands of Japan. In spite of the oligotrophy of the origin water that the Kuroshio carries, the Kuroshio water is known for spawning and feeding grounds of commercial/non-commercial fish larvae, explaining a higher fisheries production in the region. Thus, it puzzles an oceanographic and ecological relationships among nutrient fields, standing stock and productivity of organisms. In order to understand the complex Kuroshio ecosystems, phytoplankton dynamics is investigated using remote sensing data, namely phytoplankton pigment or chlorophyll-a observed by Advanced Himawari Imager (AHI) onboard Himawari-8. The area-integrated, and the area average of, Kuroshio chlorophyll-a was found predictable from a chlorophyll-a measurement in the 134-136 °E, where the Kuroshio current direction is most stable between 130-150 °E . An analysis of short term variability (< 1 year) of the Kuroshio chlorophyll-a concentration revealed that a cumulative, and monthly average of, chlorophyll-a over a month in the Kuroshio surface water could be estimated from a chlorophyll-a measurement at a single day in the month. These results suggest that there is a key spot and timing to monitor the phytoplankton activities in the Kuroshio current.