Physical and Biogeochemical Drivers of Alongshore pH and Oxygen Variability in the California Current System
Physical and Biogeochemical Drivers of Alongshore pH and Oxygen Variability in the California Current System
复制标题
DOI：
10.1029/2020gl089553
复制
发表时间：
2020-10-16
影响因子：
5.2
通讯作者：
Fiechter, Jerome
中科院分区：
文献类型：
--
作者：
Cheresh, Julia;Fiechter, Jerome
在加州洋流系统 (CCS) 中，近岸环境自然暴露于低 pH 值和因沿海上升流而导致的氧气减少。人为影响进一步将 pH 值和氧气降低到生物阈值以下，使 CCS 特别容易受到海洋酸化和缺氧的影响。物理-生物地球化学耦合模型的结果揭示了中央 CCS 近岸 pH 和氧气的强烈异质沿岸模式，无论是长期平均值还是趋势。这种空间结构可以通过当地上升流强度的沿岸变化与随后的初级生产之间的相互作用来解释，并受到近岸平流和区域地转流的调节。该模型解决方案表明，海洋酸化和缺氧的进展在空间上不会是均匀的，从而强调在评估自然和人为对东部边界洋流上升区域沿海生态系统的影响时需要考虑次区域过程。
In the California Current System (CCS), the nearshore environment experiences natural exposure to low pH and reduced oxygen in response to coastal upwelling. Anthropogenic impacts further decrease pH and oxygen below biological thresholds, making the CCS particularly vulnerable to ocean acidification and hypoxia. Results from a coupled physical-biogeochemical model reveal a strongly heterogeneous alongshore pattern of nearshore pH and oxygen in the central CCS, both in their long-term means and trends. This spatial structuring is explained by an interplay between alongshore variability in local upwelling intensity and subsequent primary production, modulated by nearshore advection and regional geostrophic currents. The model solution suggests that the progression of ocean acidification and hypoxia will not be spatially homogeneous, thereby highlighting the need to consider subregional processes when assessing natural and anthropogenic impacts on coastal ecosystems in eastern boundary current upwelling regions.