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The Greenland Ice Sheet has undergone rapid mass loss over the last four decades, primarily through solid and liquid discharge at marine‐terminating outlet glaciers. The acceleration of these glaciers is in part due to the increase in temperature of ocean water in contact with the glacier terminus. However, quantifying heat transport to the glacier through fjord circulation can be challenging due to iceberg abundance, which threatens instrument survival and fjord accessibility. Here we utilize iceberg movement to infer upper‐layer fjord circulation, as freely floating icebergs (i.e., outside the mélange region) behave as natural drifters. In the summers of 2014 and 2019, we deployed transmitting GPS units on a total of 13 icebergs in Ilulissat Icefjord, an iceberg‐rich and historically data‐poor fjord in west Greenland, to quantify circulation over the upper 0–250 m of the water column. We find that the direction of upper‐layer fjord circulation is strongly impacted by the timing of tributary meltwater runoff, while the speed of this circulation changes in concert with glacier behavior, which includes increases and decreases in glacier speed and meltwater runoff. During periods of increased meltwater runoff entering from tributary fjords, icebergs at these confluences deviated from their down‐fjord trajectory, even reversing up‐fjord, until the runoff pulse subsided days later. This study demonstrates the utility of iceberg monitoring to constrain upper‐layer fjord circulation, and highlights the importance of including tributary fjords in predictive models of heat transport and fjord circulation.

Greenland’s glaciers have been retreating, thinning and accelerating since the mid-1990s, with the mass loss from the Greenland Ice Sheet (GrIS) now being the largest contributor to global sea level rise. Monitoring changes in glacier dynamics using in-situ or remote sensing methods has been and remains therefore crucial to improve our understanding of glaciological processes and the response of glaciers to changes in climate. Over the past two decades, significant advances in technology have provided improvements in the way we observe glacier behavior and have helped to reduce uncertainties in future projections. This review focuses on advances in in-situ monitoring of glaciological processes, but also discusses novel methods in satellite remote sensing. We further highlight gaps in observing, measuring and monitoring glaciers in Greenland, which should be addressed in order to improve our understanding of glacier dynamics and to reduce in uncertainties in future sea level rise projections. In addition, we review coordination and inclusivity of science conducted in Greenland and provide suggestion that could foster increased collaboration and co-production.