Decadal changes in Gulf of Alaska upwelling source waters

作者：Buil Mercedes Pozo^*; Di Lorenzo Emanuele

来源：Geophysical Research Letters, 2015, 42(5): 1488-1495.

DOI：10.1002/2015GL063191

• decadal ocean variability
• Gulf of Alaska
• subsurface circulation
• subsurface anomalies
• upper ocean temperature

Decadal changes in sea surface temperature (SST) in the Gulf of Alaska are linked to long-term transitions in the marine ecosystem. While previous studies have identified the atmospheric variability of the Aleutian Low as an important driver of Ekman pumping and low-frequency SST anomalies, the role of subsurface gyre-scale dynamics remains unexplored. Using a set of reanalysis data sets from 1958 to the present, we find that subsurface temperature anomalies generated along the North Pacific Current significantly contribute through mean upwelling to decadal changes of SST in the Gulf of Alaska. This influence is comparable to the contribution associated with variations in atmospheric winds. Given the exceptional low-frequency character of the propagation of subsurface anomalies (e.g., multidecadal) along the gyre, monitoring subsurface temperature anomalies up stream along the North Pacific Current may enhance the decadal predictability of SST in the Gulf of Alaska and its impact on local marine ecosystems.

• 出版日期2015-3-16