Surface chlorophyll concentrations inferred from satellite images suggest a strong influence of the mesoscale activity on biogeochemical variability within the oligotrophic regions of the Gulf of Mexico (GoM). More specifically, long-living anticyclonic Loop Current eddies (LCEs) are shed episodically from the Loop Current and propagate westward. This study addresses the biogeochemical response of the LCEs to seasonal forcing and show their role in driving phytoplankton biomass distribution in the GoM. Using an eddy resolving ($\mathrm{1}/\mathrm{12}$^∘) interannual regional simulation, it is shown that the LCEs foster a large biomass increase in winter in the upper ocean. It is based on the coupled physical–biogeochemical model NEMO-PISCES (Nucleus for European Modeling of the Ocean and Pelagic Interaction Scheme for Carbon and Ecosystem Studies) that yields a realistic representation of the surface chlorophyll distribution. The primary production in the LCEs is larger than the average rate in the surrounding open waters of the GoM. This behavior cannot be directly identified from surface chlorophyll distribution alone since LCEs are associated with a negative surface chlorophyll anomaly all year long. This anomalous biomass increase in the LCEs is explained by the mixed-layer response to winter convective mixing that reaches deeper and nutrient-richer waters.

中文翻译：

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Loop Current 涡流会刺激墨西哥湾的生产力吗？

从卫星图像推断的表面叶绿素浓度表明，中尺度活动对墨西哥湾 (GoM) 贫营养区域内的生物地球化学变异有很大影响。更具体地说，长寿命的反气旋环流涡流 (LCE) 从环流中偶发地脱落并向西传播。这项研究解决了 LCE 对季节性强迫的生物地球化学反应，并展示了它们在推动 GoM 浮游植物生物量分布方面的作用。使用涡旋解析 ($\mathrm{1}/\mathrm{12}$^∘ ) 年际区域模拟表明，LCEs 在冬季促进了上层海洋生物量的大量增加。它基于耦合的物理-生物地球化学模型 NEMO-PISCES（欧洲海洋建模核心和碳和生态系统研究的远洋相互作用计划），可产生表面叶绿素分布的真实表现。LCEs 的初级产量大于 GoM 周围开放水域的平均速率。这种行为不能仅从表面叶绿素分布直接识别，因为 LCE 与全年负表面叶绿素异常相关。LCE 中这种异常的生物量增加可以通过混合层对冬季对流混合的响应来解释，这些对流混合到达更深、营养更丰富的水域。