We conducted a ship observation of two anticyclonic mesoscale eddies (Eddies A and B) between June and July 2016 in the offshore region of the western subarctic North Pacific to clarify the impact of anticyclonic eddies on biological production. Analysis of satellite data reveals that Eddy A formed south of the Alaskan Peninsula on May 2011 while Eddy B formed in the observation area on November 2015. Iron concentration was low both inside and outside Eddies A and B, and there were no large differences between chlorophyll a (chl-a) concentration inside and outside eddies. Satellite-derived chl-a concentration inside Eddy A had been high compared with that in the surrounding area when the eddy was located along the Aleutian Islands and just after it detached from the islands, suggesting that iron originating from the coastal region was consumed during the two-year journey from the coastal region to the observation area. Field measurements also reveal that vertical diffusivity was low both inside and outside Eddies A and B, which could be another factor underlying low iron both inside and outside Eddies A and B and small differences between chl-a concentration inside and outside the eddies.

中文翻译：

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西亚北极北太平洋反气旋涡旋的观测

我们于 2016 年 6 月至 7 月在西亚北极北太平洋近海地区对两个反气旋中尺度涡旋（涡旋 A 和 B）进行了船舶观测，以阐明反气旋涡旋对生物生产的影响。卫星资料分析表明，涡流A于2011年5月在阿拉斯加半岛以南形成，涡流B于2015年11月在观测区形成。 a (chl-a) 涡流内外的浓度。与涡流位于阿留申群岛沿岸和刚从岛屿分离后的周边地区相比，涡流 A 内部的卫星衍生 chl-a 浓度较高，表明在从沿海地区到观察区的两年旅程中消耗了来自沿海地区的铁。现场测量还表明，涡流 A 和 B 内外的垂直扩散率都很低，这可能是造成涡流 A 和 B 内外铁含量低以及涡流内外 chl-a 浓度差异很小的另一个因素。