Bedrock and soils

The role of ice sheets in global biogeochemical cycles

Climate change is amplified in polar regions. As a consequence, ice sheets and glaciers (and in particular the Greenland Ice Sheet) are currently experiencing record melting, resulting in a significant increase of already substantial summer freshwater fluxes to the ocean. While the physical consequences of this freshwater input, as well as its alarming increase have been intensively studied, its biogeochemical dimension remains poorly understood.

Once thought to be devoid of life, mounting evidence suggests that subglacial environments are incredibly active biogeochemical reactors that supply globally significant fluxes of labile, bio-essential nutrients including iron, phosphorus, nitrogen, silica and carbon to key ocean regions. Yet, the controls on the nature, magnitude and timing of these export fluxes and, as a consequence, their response to projected climate change are poorly understood. This knowledge gap is critical because it not only limits our ability to fully evaluate the role of ice sheets and glaciers in the evolution of global biogeochemical cycles and climate, but also the socio-economic impacts of alarming ice retreat.

Therefore, we develop and apply, in close collaboration with observationalists, novel mechanistic models to investigate biogeochemical dynamics on, in and beneath ice shields, to evaluate their role for global biogeochemical cycles, and their response to projected climate change.

Relevant project(s): NuttI

People involved: Sandra Arndt, Frank Pattyn

Key publications:

  • Lamarche-Gagnon, G., Wadham, J.L, Sherwood Lollar, B., Arndt, S., Lacrampe-Couloume, G., Fietzek, P., Beaton, A., Tedstone, A., Telling, J., Bagshaw, E.A., Hawkings, J.R., Kohler, T., Zarsky, J., Stibal, M., Mowlem, M.C., 2018. Continuous pulsed export of methane-supersaturated runoff from the Greenland Ice Sheet, Nature, accepted
  • Wadham, J.L., S. Arndt, S. Tulaczyk, M, Stibal, M. Tranter, A., Ridgwell, J. Telling, E. Lawson, A. Dubnick, M.J. Sharp, A.M Anesio, C. Butler. 2012, Potential methane reserves beneath Antarctica, Nature, 488, 633-637.
  • The role of fungi in biogeochemical cycles and rock weathering

    Water-rock interactions

    Soil pollution