The study introduces the North Pacific Gyre Oscillation (NPGO) as a new pattern of climate change that links ocean climate and ecosystem dynamics in the Northeast Pacific. The NPGO is distinct from the Pacific Decadal Oscillation (PDO) and is significantly correlated with unexplained fluctuations in salinity, nutrients, and chlorophyll. The NPGO is driven by regional and basin-scale variations in wind-driven upwelling and horizontal advection, which control salinity and nutrient concentrations. Nutrient fluctuations lead to changes in phytoplankton concentrations and potentially higher trophic levels. The NPGO extends beyond the North Pacific and is part of a global-scale climate variability pattern evident in sea level trends and sea surface temperatures. The amplification of NPGO variance in observations and global warming simulations suggests it may play an increasingly important role in forcing decadal changes in marine ecosystems. The study uses empirical orthogonal function (EOF) techniques and a high-resolution ocean model to analyze the NPGO and its relationship with the PDO, and finds that the NPGO is statistically independent of the PDO. The NPGO is also linked to changes in coastal upwelling and nutrient fluxes, which are crucial for ecosystem dynamics. The spatial patterns of the NPGO are symmetric across the equator, indicating tropical coupled dynamics involved in its variability. The observed strengthening of the NPGO since 1993 may be a response to anthropogenic forcing and global warming, and further research is needed to understand its implications for future climate and ecosystem changes.The study introduces the North Pacific Gyre Oscillation (NPGO) as a new pattern of climate change that links ocean climate and ecosystem dynamics in the Northeast Pacific. The NPGO is distinct from the Pacific Decadal Oscillation (PDO) and is significantly correlated with unexplained fluctuations in salinity, nutrients, and chlorophyll. The NPGO is driven by regional and basin-scale variations in wind-driven upwelling and horizontal advection, which control salinity and nutrient concentrations. Nutrient fluctuations lead to changes in phytoplankton concentrations and potentially higher trophic levels. The NPGO extends beyond the North Pacific and is part of a global-scale climate variability pattern evident in sea level trends and sea surface temperatures. The amplification of NPGO variance in observations and global warming simulations suggests it may play an increasingly important role in forcing decadal changes in marine ecosystems. The study uses empirical orthogonal function (EOF) techniques and a high-resolution ocean model to analyze the NPGO and its relationship with the PDO, and finds that the NPGO is statistically independent of the PDO. The NPGO is also linked to changes in coastal upwelling and nutrient fluxes, which are crucial for ecosystem dynamics. The spatial patterns of the NPGO are symmetric across the equator, indicating tropical coupled dynamics involved in its variability. The observed strengthening of the NPGO since 1993 may be a response to anthropogenic forcing and global warming, and further research is needed to understand its implications for future climate and ecosystem changes.