EGU22-4926
https://doi.org/10.5194/egusphere-egu22-4926
EGU General Assembly 2022
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.

Is longer or warmer melt season a more important driver of ice dynamics.

Basile de Fleurian1, Richard Davy2, and Petra M. Langebroek3
Basile de Fleurian et al.
  • 1University of Bergen and Bjerknes centre, Deparment for Earth Science, Bergen, Norway (basile.defleurian@uib.no)
  • 2Nansen Environmental and Remote Sensing Centre, Bjerknes Centre for Climate Research, Bergen, NORWAY
  • 3NORCE Norwegian Research Centre AS, Bjerknes Centre for Climate Research, Bergen, NORWAY

In recent years, temperatures over the Greenland ice sheet have been rising, leading to an increase in surface melt. This increase however can not be reduced to a simple number. Throughout the recent years we have seen some extreme melt seasons with melt extending over the whole surface of the ice sheet (2012) or melt seasons of lower amplitudes but with a longer duration (2010). The effect of those variations on the subglacial system and hence on ice dynamic are poorly understood and are still mainly deduced from studies based on mountain glaciers.

Here we apply the Ice-sheet and Sea-level System Model (ISSM) to a synthetic glacier with a geometry similar to a Greenland ice sheet land terminating glacier. The forcing is designed such that it allows to investigate different characteristics of the melt season such as its length or intensity. Subglacial hydrology and ice dynamics are coupled within ISSM allowing to study the response of the system in terms of subglacial water pressure and the final impact on ice dynamics. Of particular interest is the evolution of the distribution of the efficient and inefficient component of the subglacial drainage system which directly impacts the water pressure evolution at the base of the glacier. We note that the initiation of the melt season and the intensity of the melt at this period is a crucial parameter when studying the dynamic response of the glacier to different melt season characteristics.

From those results, we can infer a more precise evolution of the dynamics of land terminating glaciers that are heavily driven by their subglacial drainage system. We also highlight which changes in the melt season pattern would be the most damageable for glacier stability in the future.

How to cite: de Fleurian, B., Davy, R., and Langebroek, P. M.: Is longer or warmer melt season a more important driver of ice dynamics., EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-4926, https://doi.org/10.5194/egusphere-egu22-4926, 2022.