The Alaskan Arctic regime shift since 2017: A harbinger of years to come?

Recent fingerprints of Alaskan Arctic climate change include new weather patterns whose impacts propagate through the marine ecosystem. Multiple lines observational evidence draw attention to last five years (2017–2021) as a remarkable period change. Bering Sea winter and spring ice coverage was remarkably low in 2018 2019 associated with shifted Aleutian Low (AL) into western Sea, ridging overlying polar jet stream (PJS) that supported southerly winds reduced growth. The climatological Beaufort High Gyre saw multiple winter-long collapses (2017 2020), only two such events modern reanalysis era. In contrast, from 2012 2016 AL PJS were located southeastward across Gulf Alaska, which sea recent collocation exposed ocean surface atmospheric anomalies supports emergence regional circulation response sea-ice loss. We propose system shift after 2017 foreshadows beginning an increasing frequency major loss – floods, delayed blooms, food chain disruptions is sooner than projected by models.