This study demonstrates the connection between two important parts of the climate system: atmospheric conditions over the Greenland Ice Sheet and the seasonal ice flow of glaciers -- specifically a glacier in Southwest Greenland. The authors use GPS measurements to identify more than 40 cases of speed up of the glacier. The majority of the observed speed up can be linked to the melting of the surface of the ice. In particular, the study shows that atmospheric rivers are linked to the strongest speed-up events. The findings have implications for the future dynamics of Greenlandic glaciers as weather patterns change intensity in response to the warming climate.