LATTICE: Land-terminating ice cliffs in North Greenland: processes, divers and their relation to regional climate
Land-terminating ice cliffs (LTIC) are relatively anomalous features of the cryosphere and their common pillar of occurrence are cold and dry climatic conditions. In North Greenland the terrestrial ice margin forms numerous LTICs, but only the Red Rock ice cliff experienced extensive past research. Over the last six decades the ice cliff was thinning but concurrently showed periods of advance, retreat and re-advance. This counterintuitive behaviour of advancing and simultaneously thinning remained unstudied in detail so far and invites the question of driving processes.
We argue that changes of the Red Rock ice cliff reflect climate variability as changes in either the accumulation or ablation components or both. Therefore, we hypothesize that any changes of the ice cliff is a climate indicator for the atmosphere-cryosphere relation in North Greenland. If the interaction of the ice cliff with the atmosphere is understood, changes of the ice cliff can be translated into a climate signal. The footprint of this signal has relevance for a large portion of cold and dry North Greenland.
We investigate in detail the processes governing the changes of the ice cliff, its morphology, position and thickness. Applying in-situ based measurements and process orientated modelling we are able to resolve the ice flux, quantify frontal calving and study the sensitivity of the energy and mass balance to climate. From past and future ice temperature measurements combined with ice dynamic modelling we investigate, if a possible warming of the ice may have influenced the observed cliff advance. From energy and mass balance modelling we will quantify the climate sensitivity of the two mass balance regimes – the rather flat glacier upstream the ice cliff and the cliff front itself. Both regimes respond differently to mainly moisture controlled atmospheric conditions.
Beyond a sensitivity to air temperature, we assume that the ice cliff mass balance shows significant sensitivities to moisture related atmospheric variables, referring to a projected wetter Arctic. On the larger picture, relating the local scale drivers to meso-scale modes of climate variability will increase our knowledge about atmosphere-cryosphere-ocean connection in North Greenland, which is a sensitive region for the global climate.
FWF (Grant No. P 36306)
10/2023 - 01/2027