In the subtropical ocean, physical and biogeochemical patchiness exists across a range of spatial and temporal scales. As ocean surface temperatures rise, climate models suggest that the strength of the basin-scale biological carbon pump may diminish due to increased stratification and depleted surface nutrients. However, global model predictions often cannot account for climate-physical-ecosystem interactions occurring at finer spatial scales (e.g., less than a few tens of kilometers). In order to study such fine-scale interactions, we developed a computationally tractable, idealized modeling framework that allows for a systematic assessment of the impact of fine-scale frontal disturbances (i.e., short-lived upwelling and downwelling events) on biogeochemical and ecosystem dynamics. The model successfully captured both the mean dynamics and the range of ecosystem variability observed at the Hawaii Ocean Time-series (HOT) site in the oligotrophic North Pacific Subtropical Gyre. Fine-scale frontal disturbances were shown to impact both phytoplankton assemblages and carbon cycling. Specifically, disturbances of shorter duration but higher intensity favored the growth of large phytoplankton and contributed to elevated carbon export efficiency. However, for disturbances of longer duration and higher intensity, a decoupling between physical changes and biological responses led to a reduced utilization efficiency of upwelled nutrients and thus a reduction in new production. Our results emphasize that future changes in both large and fine-scale physical dynamics may play an important role in shaping marine ecosystems, and could be accounted for in the next-generation global climate models using this type of parameterization.

在亚热带海洋中，物理和生物地球化学斑块存在于一系列时空尺度上。随着海洋表面温度的升高，气候模型表明，由于分层增加和地表养分减少，流域规模的生物碳泵的强度可能会降低。但是，全球模型预测通常不能解释在更精细的空间尺度（例如，少于几十公里）上发生的气候-物理-生态系统相互作用。为了研究这种细微的相互作用，我们开发了一个易于计算的，理想化的建模框架，可以系统地评估细微的额叶扰动（即短暂的上升和下降事件）对生物地球化学和生态系统动力学的影响。 。该模型成功捕获了贫营养北太平洋亚热带环流的夏威夷海洋时间序列（HOT）站点上观测到的平均动力学和生态系统变异性范围。研究表明，小规模的额叶扰动会影响浮游植物的组装和碳循环。具体而言，持续时间较短但强度较高的干扰有利于大型浮游植物的生长，并有助于提高碳出口效率。然而，对于持续时间更长，强度更高的干扰，物理变化和生物学响应之间的解耦导致上升营养素的利用效率降低，从而减少了新产量。我们的结果强调，未来大规模和精细物理动力学的变化可能会在塑造海洋生态系统中发挥重要作用，