Unraveling ocean dynamics in Northwest Greenland Fjords.

We investigated the relative contributions of various factors that influence seasonal changes in sea surface partial pressure of ( , calculated from the measured pH and total alkalinity) in four regions of northwestern Greenland: Nares Strait, Lincoln Sea, Sherard Osborn and Petermann fjords. Using the temperature minimum layer as a proxy for winter conditions, we examined dynamics from the onset of sea-ice melt to summer. Our findings revealed significant spatial variability in , driven by differences in temperature, freshwater inputs, and biological activity. In particular, in Sherard Osborn Fjord substantial freshwater inputs and strong stratification were found to enhance accumulation, while in Petermann Fjord biological uptake was the main driver. This study, conducted in summer 2019, underscores the critical role of northwest Greenland's coastal waters as a summer sink. It highlights the complex interplay of physical and biogeochemical processes in modulating , suggesting significant regional differences in dynamics between two neighboring fjords.