IPEV Greenland

The independent alpine mountain glaciers of the Greenland Ice Sheet (GrIs), comprising around 18,500 features in Greenland, are highly sensitive to climatic variations. They are excellent targets for documenting glacier fluctuations during the Holocene and exploring the forcing factors responsible for their evolution. However, little is known about their evolution, which can be studied by dating moraines with cosmic ray exposure (CRE) ages.

Recent advances have revealed an asynchronous evolution as a function of latitude. On eastern Greenland, north of 65°N, the alpine glaciers recorded their greatest Holocene advance, i.e. their maximum extension at the beginning of the Holocene. In contrast, the few data south of 65°N on eastern Greenland, whether from mountain glaciers, GrIs or lake sediments, suggest that the maximum extension of the Holocene occurred at the end of the Holocene, with the exception of a few cases.

We suspect that this difference in the behaviour of mountain glaciers in eastern Greenland is linked to the effects of ocean currents on local climatic conditions. On the basis of these hypotheses, we plan to document the evolution of four local glaciers using CRE moraine dating. The Holocene moraines of two selected glaciers near Narsarsuak and two other glaciers near Sisimiut will be studied.

The samples collected in the field will be analysed in the Cerege laboratory. The links between glacier fluctuations and regional climatic conditions will be studied by compiling indirect climate data and changes in temperature and precipitation from two transient climate models (LOVECLIM and TrAce) using different forcing experiments (C02, volcanism, insolation, AMOC changes ....).