Deutsch
 
Datenschutzhinweis Impressum
  DetailsucheBrowse

Datensatz

DATENSATZ AKTIONENEXPORT

Freigegeben

Zeitschriftenartikel

Stabilizing effect of mélange buttressing on the marine ice-cliff instability of the West Antarctic Ice Sheet

Urheber*innen
/persons/resource/Tanja.Schlemm

Schlemm,  Tanja
Potsdam Institute for Climate Impact Research;

/persons/resource/johannes.feldmann

Feldmann,  Johannes
Potsdam Institute for Climate Impact Research;

/persons/resource/Ricarda.Winkelmann

Winkelmann,  Ricarda
Potsdam Institute for Climate Impact Research;

/persons/resource/Levermann

Levermann,  Anders
Potsdam Institute for Climate Impact Research;

Externe Ressourcen
Es sind keine externen Ressourcen hinterlegt
Volltexte (frei zugänglich)

26925oa.pdf
(Verlagsversion), 13MB

Ergänzendes Material (frei zugänglich)
Es sind keine frei zugänglichen Ergänzenden Materialien verfügbar
Zitation

Schlemm, T., Feldmann, J., Winkelmann, R., Levermann, A. (2022): Stabilizing effect of mélange buttressing on the marine ice-cliff instability of the West Antarctic Ice Sheet. - The Cryosphere, 16, 5, 1979-1996.
https://doi.org/10.5194/tc-16-1979-2022


Zitierlink: https://publications.pik-potsdam.de/pubman/item/item_26925
Zusammenfassung
Due to global warming and particularly high regional ocean warming, both Thwaites and Pine Island glaciers in the Amundsen region of the Antarctic Ice Sheet could lose their buttressing ice shelves over time. We analyze the possible consequences using the Parallel Ice Sheet Model (PISM), applying a simple cliff-calving parameterization and an ice-mélange-buttressing model. We find that the instantaneous loss of ice-shelf buttressing, due to enforced ice-shelf melting, initiates grounding line retreat and triggers the marine ice sheet instability (MISI). As a consequence, the grounding line progresses into the interior of the West Antarctic Ice Sheet and leads to a sea level contribution of 0.6 m within 100 a. By subjecting the exposed ice cliffs to cliff calving using our simplified parameterization, we also analyze the marine ice cliff instability (MICI). In our simulations it can double or even triple the sea level contribution depending on the only loosely constraint parameter which determines the maximum cliff-calving rate. The speed of MICI depends on this upper bound on the calving rate which is given by the ice mélange buttressing the glacier. However, stabilization of MICI may occur for geometric reasons. Since the embayment geometry changes as MICI advances into the interior of the ice sheet, the upper bound on calving rates is reduced and the progress of MICI is slowed down. Although we cannot claim that our simulations bear relevant quantitative estimates of the effect of ice-mélange buttressing on MICI, the mechanism has the potential to stop the instability. Further research is needed to evaluate its role for the past and future evolution of the Antarctic Ice Sheet.