The northeastern pacific (NEP) encompasses the gulf of alaska (GOALME) and the california current large marine ecosystems (CCLME)

A common driver of variability in both systems is the north pacific current (NPC), which forms the transition between the subarctic and subtropical gyres and bifurcates near the north american coast into the northward-flowing alaska current (AC) and southward-flowing california current (CC). Variability in the strength and latitudinal position of the NPC, and its bifurcation, thus determines the physical and biogeochemical properties of the waters entering the GOALME and CCLME, with significant downstream ecosystem impacts. A poleward shift in the position of the NPC is a particularly robust feature in global climate models, and is projected to greatly impact regional trends in CC upwelling. This poleward shift is, in turn, projected to be reflected in the shifting distribution of sardine populations and core top predator habitat. Given the importance of the NPC variability, the overarching goal of this project is to investigate its historical role in providing connectivity between the GOALME and CCLME, assess its predictability on seasonal to interannual time scales, project its future variability, and explore the downstream ecosystem impacts in the coastal waters of the GOALME and CCLME across these timescales. We will analyze a set of high-resolution reanalyses and hindcasts, and outputs from retrospective near-term forecasts and future climate projections to: (1) understand the historical variability and changes in water mass properties, transport, and bifurcation latitude of the NPC and its connections to coastal waters along the CCS and GOA, (2) quantify and diagnose drivers of near-term forecast skill and predictability in the NPC, its bifurcation, and its downstream physical and biogeochemical properties, and (3) understand and examine how a projected future poleward shift of the NPC might alter water mass properties and transport and their downstream impacts. Key elements of the work plan are to: (1) examine the historical variability and the connectivity between the GOA and CCS coastal waters through the large-scale variability of the NPC and its bifurcation, (2) quantify and diagnose near-term predictability and forecast skill using the CESM2 seasonal-to-multiyear large ensemble (SMYLE), and (3) evaluate and examine the robustness of future changes and downstream impacts of the NPC in the CESM2 large ensemble community project (LENS2).