Earth's internal heat drives rapid ice flow, subglacial melting in Greenland
|Conceptual view of the interplay between the mantle and the Greenland Ice |
Sheet across the plume track [Credit: A. Petrunin, GF]
The team of geoscientists has now, for the first time, been able to prove strong coupling between processes deep in Earth's interior with the flow dynamics and subglacial hydrology of large ice sheets: "The geothermal anomaly which resulted from the Icelandic mantle-plume tens of millions of years ago is an important motor for today's hydrology under the ice sheet and for the high flow-rate of the ice," explains Irina Rogozhina. "This, in turn, broadly influences the dynamic behavior of ice masses and must be included in studies of the future response to climate change."
|Present-day location of the Iceland plume and zones of the mantle plume-induced |
thinning of the lithosphere and active melting at the ice base
[Credit: A. Petrunin, GFZ]
This unexpected link between hotspot history and ice sheet behavior shows that the influences on ice sheets span a huge range of timescales from the month by month changes of the ice cover to the multi-million year epochs over which Earth's mantle and tectonic plates evolve. Besides this, the results of the study provide an independent test for models of the opening of the North Atlantic which after a three-decade-long debate still is not fully understood.
The findings are published in Nature Geoscience.
Source: Helmholtz Centre Potsdam - GFZ German Research Centre for Geosciences [April 04, 2016]