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The coastal circulation around Southern Greenland transports fresh, buoyant water masses from the Arctic and Greenland Ice Sheet near regions of convection, sinking, and deep-water formation in the Irminger and Labrador Seas. Here, we track the pathways and fate of these fresh water masses by initializing synthetic particles in the East Greenland Coastal Current on the Southeast Greenland shelf and running them through altimetry-derived surface currents from 1993 to 2021. We report that the majority of waters (83%) remain on the shelf around the southern tip of Greenland. Variability in the shelf-basin exchange of the remaining particles closely follows the number of tip jet wind events on seasonal and interannual timescales. The probability of a particle exiting the shelf increases almost fivefold during a tip jet event. These results indicate that the number of tip jets is a close proxy of the shelf-basin exchange around Southern Greenland. [ABSTRACT FROM AUTHOR]

As well as having an impact on the background state of the climate, global warming due to human activities could affect its natural oscillations and internal variability. In this study, we use four initial-condition ensembles from the CMIP6 framework to investigate the potential evolution of internal climate variability under different warming pathways for the twenty-first century. Our results suggest significant changes in natural climate variability and point to two distinct regimes driving these changes. The first is a decrease in internal variability of surface air temperature at high latitudes and all frequencies, associated with a poleward shift and the gradual disappearance of sea ice edges, which we show to be an important component of internal variability. The second is an intensification of the interannual variability of surface air temperature and precipitation at low latitudes, which appears to be associated with El Niño–Southern Oscillation (ENSO). This second regime is particularly alarming because it may contribute to making the climate more unstable and less predictable, with a significant impact on human societies and ecosystems. [ABSTRACT FROM AUTHOR]

A novel framework for comparing Lagrangian and gridded Eulerian velocity fields is proposed. The method involves three steps that individually leverage the strengths of each reference frame to provide robust intercomparisons, while also allowing the user to adapt the individual steps to the process of interest. The utility of the methodology is then demonstrated by applying it to a comparison between a set of 34 Lagrangian surface drifters deployed on the continental shelf around the southern tip of Greenland and Eulerian altimetry-derived surface currents with and without Ekman velocities. We conclude that the methodology sufficiently addresses differences between the reference frames and accurately identifies errors when they exist. This result enables us to conclude that the altimetry-derived surface currents accurately resolve the important components of the shelf circulation around the southern tip of Greenland and can be used to track pathways of fresh water around Greenland. [ABSTRACT FROM AUTHOR]