Constraining ice cap extents during past interglacials from cosmogenic exposure dating and inverse modeling
Ice mass loss from Greenland has accelerated over the last decades and it has recently been predicted that Greenland could potentially become ice free within the next millennium. During past interglacial periods, when global mean temperatures reached values larger than today, the Greenland Ice Sheet and local ice caps in Greenland were most likely smaller than their current extent, but current information is sparse. Knowledge about how the Greenland Ice Sheet and local ice caps responded to climate changes in the past is therefore of crucial importance to put the current changes into context. This project, “Constraining ice cap extent during past interglacials from cosmogenic exposure dating and inverse modelling”, aims at constraining the extent of local ice caps during past interglacial periods, to reveal their sensitivity to past climate changes. During fieldwork, we will collect sediment samples from meltwater streams in front of local ice caps in the Narsarsuaq region, South Greenland. Within these sediment samples, we will measure the content of cosmogenic isotopes (10Be, 26Al and 14C), formed within the minerals by the collision of cosmogenic ray particles with the surface of the Earth, during periods of exposure (limited ice extent). Combining isotope concentrations with inverse modelling, we will get a model output which shows the most likely extent or absence of ice caps during past interglacial periods. We will then combine the model output with geological mapping and field observations to support interpretation of the sample results and hope to obtain new and extended knowledge on ice cap sensitivity to climate changes during interglacial periods.
|Location||Narsarsuaq, South Greenland|
|Funded amount||17,083 CHF|
|Project dates||1st June 2022 – 31st August 2022|
|Category||Polar Access Fund|