Role of Geostrophic Currents in Future Changes of Coastal Upwelling in the California Current System

作者：Hui Ding, Michael A. Alexander, Michael G. Jacox · 发表于：Geophysical Research Letters · 年份：2020 · DOI：10.1029/2020gl090768 · 被引用次数：21 · 研究领域：Oceanographic and Atmospheric Processes、Climate variability and models、Marine and coastal ecosystems

Abstract Given the importance of coastal upwelling in the California Current System (CCS), there is a considerable interest in predicting its response to global warming. However, upwelling changes are often treated as synonymous with changes in upwelling‐favorable winds, while the role of geostrophic transport is unaccounted for. Here, we examine the respective roles of Ekman and geostrophic transports using the Community Earth System Model Large Ensemble. In some parts of the CCS, the contribution of geostrophic transport to long‐term changes in upwelling is equal or greater than the contribution from Ekman transport. The combination of the two transports nearly close the momentum budget, and thus reproduce the mean state, interannual variability, and long‐term changes in upwelling. These results highlight the importance of accounting for ocean circulation when quantifying upwelling and its variability and change.