Through the Greenfjord project, Jérôme and his team from the SENSE laboratory (Smart Sensors for Extreme Environments) at EPFL wish to determine whether subglacial meltwater constitutes sources significant of GHG. This subglacial meltwater is produced between the melting glacier and the bedrock. More specifically, Jérôme is trying to determine whether the Greenland ice sheet is a significant source of naturally occurring methane. Could this phenomenon get worse with global warming and the retreat of glaciers?
With FOREL, the objective is therefore to get as close as possible to the glacier, and to catch its meltwater several hundred meters deep, in order to analyze the composition.
Discovery and scientific enigma raised on board FOREL:
“Before sending the Sub Ocean probe into the water, the CTD is deployed to continuously measure temperature, salinity, the quantity of dissolved oxygen, turbidity (amount of particles in the water) and chlorophyll. Chlorophyll is a very good indicator of biological activity in water. And over the different days of deployment in the fjord with FOREL, we observed peaks of chlorophyll around ten meters below the surface and systematically we also observed peaks of dissolved methane. This is a surprise because methane is a gas which mainly occurs in environments poor in oxygen while we were in a fjord rich in oxygen. This discovery raises questions about the biological mechanisms and the type of algae that could produce this methane at around 10 m above the surface in this greenlandic fjord. We have a scientific enigma to solve…” Jérôme Chappellaz.
Jérome Chappellaz is a full Prof at EPFL (Ecole polytechnique fédérale de Lausanne). Director of research CNRS. Co-Founder and Chairman of the Ice Memory Foundation.
Photo : @julien.girardot.photography