I am currently working on a project investigating how water flows under the Greenland Ice Sheet. There are two main approaches: (1) field-based experiments where we use chemical tracers to measure the speed and dispersivity of melt water as it travels under the ice sheet, and (2) numerical modelling, to predict how channels that carry meltwater under the ice might evolve with time. Changes in properties of the subglacial meltwater channels will be compared with surface-based observations of ice flow, to assess the link between subglacial channel evolution and ice sheet motion. Results from this work will hopefully give us a better idea of how to include changes in ice sheet hydrology in much larger-scale numerical models that predict ice sheet response to climate change.