TY - JOUR
T1 - Remote control of Filchner‐Ronne Ice Shelf melt rates by the Antarctic Slope Current
AU - Bull, Christopher Y. S.
AU - Jenkins, Adrian
AU - Jourdain, Nicolas C.
AU - Vaňková, Irena
AU - Holland, Paul R.
AU - Mathiot, Pierre
AU - Hausmann, Ute
AU - Sallée, Jean‐Baptiste
N1 - Funding Information: The authors would like to thank David R. Munday, Antony Siahaan, and Xylar Asay‐Davis for helpful discussions while setting up the modelling configuration and running G07‐JRA. This research was supported by the UK Natural Environment Research Council (NERC) through the Filchner Ice Shelf System project (NE/L013770/1) and the European Union's Horizon 2020 research and innovation programme under grant agreement no. 820575 (TiPACCs). N. Jourdain is funded by the French National Research Agency (ANR) through the TROIS‐AS project (ANR‐15‐CE01‐0005‐01). I. Vaňková received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska‐Curie grant (agreement 790062). J. B. Sallée and U. Hausmann were funded by the European Research Council (ERC) under the European Union‘s Horizon 2020 research and innovation program (grant agreement 637770). U. Hausmann moreover acknowledges funding by CNES. The authors also acknowledge the JWCRP Joint Marine Modelling Programme for providing support and access to model configurations and output. The authors thank Ronja Reese for advice on the use of buttressing flux response numbers from Reese, Gudmundsson et al. ( 2018 ) and Jeremie Mouginot for kindly sharing data from (Rignot et al., 2013 ). The authors thank Xylar Asay‐Davis for his detailed review feedback and interest, which contributed to the quality of this manuscript. The authors also thank an anonymous reviewer for their constructive comments.
PY - 2021/2
Y1 - 2021/2
N2 - Recent work on the Filchner‐Ronne Ice Shelf (FRIS) system has shown that a redirection of the coastal current in the southeastern Weddell Sea could lead to a regime change in which an intrusion of warm Modified Circumpolar Deep Water results in large increases in the basal melt rate. Work to date has mostly focused on how increases in the Modified Circumpolar Deep Water crossing the continental shelf break leads directly to heat driven changes in melting in the ice‐shelf cavity. In this study, we introduce a Weddell Sea regional ocean model configuration with static ice shelves. We evaluate a reference simulation against radar observations of melting, and find good agreement between the simulated and observed mean melt rates. We analyse 28 sensitivity experiments that simulate the influence of changes in remote water properties of the Antarctic Slope Current on basal melting in the FRIS. We find that remote changes in salinity quasi‐linearly modulate the mean FRIS net melt rate. Changes in remote temperature quadratically vary the FRIS net melt rate. In both salinity and temperature perturbations, the response is rapid and transient, with a recovery time‐scale of 5‐15 years dependent on the size/type of perturbation. We show that the two types of perturbations lead to different changes on the continental shelf, and that ultimately different factors modulate the melt rates in the FRIS cavity. We discuss how these results are relevant for ocean hindcast simulations, sea level, and melt rate projections of the FRIS.
AB - Recent work on the Filchner‐Ronne Ice Shelf (FRIS) system has shown that a redirection of the coastal current in the southeastern Weddell Sea could lead to a regime change in which an intrusion of warm Modified Circumpolar Deep Water results in large increases in the basal melt rate. Work to date has mostly focused on how increases in the Modified Circumpolar Deep Water crossing the continental shelf break leads directly to heat driven changes in melting in the ice‐shelf cavity. In this study, we introduce a Weddell Sea regional ocean model configuration with static ice shelves. We evaluate a reference simulation against radar observations of melting, and find good agreement between the simulated and observed mean melt rates. We analyse 28 sensitivity experiments that simulate the influence of changes in remote water properties of the Antarctic Slope Current on basal melting in the FRIS. We find that remote changes in salinity quasi‐linearly modulate the mean FRIS net melt rate. Changes in remote temperature quadratically vary the FRIS net melt rate. In both salinity and temperature perturbations, the response is rapid and transient, with a recovery time‐scale of 5‐15 years dependent on the size/type of perturbation. We show that the two types of perturbations lead to different changes on the continental shelf, and that ultimately different factors modulate the melt rates in the FRIS cavity. We discuss how these results are relevant for ocean hindcast simulations, sea level, and melt rate projections of the FRIS.
KW - Antarctica
KW - ice shelf
KW - Weddell Sea
KW - Filchner‐Ronne
KW - NEMO
KW - Antarctic Slope Current
UR - http://www.scopus.com/inward/record.url?scp=85101590482&partnerID=8YFLogxK
U2 - 10.1029/2020jc016550
DO - 10.1029/2020jc016550
M3 - Article
SN - 2169-9275
VL - 126
JO - Journal of Geophysical Research: Oceans
JF - Journal of Geophysical Research: Oceans
IS - 2
M1 - e2020JC016550
ER -