Reduced Deep Convection and Bottom Water Formation Due To Antarctic Meltwater in a Multi-Model Ensemble

Jia Jia Chen; Neil C. Swart; Rebecca Beadling; Xuhua Cheng; Tore Hattermann; André Jüling; Qian Li; John Marshall; Torge Martin; Morven Muilwijk; Andrew G. Pauling; Ariaan Purich; Inga J. Smith; Max Thomas

doi:10.1029/2023GL106492

Reduced Deep Convection and Bottom Water Formation Due To Antarctic Meltwater in a Multi-Model Ensemble

Jia Jia Chen, Neil C. Swart, Rebecca Beadling, Xuhua Cheng, Tore Hattermann, André Jüling, Qian Li, John Marshall, Torge Martin, Morven Muilwijk, Andrew G. Pauling, Ariaan Purich, Inga J. Smith, Max Thomas

School of Earth Atmosphere and Environment

Research output: Contribution to journal › Article › Research › peer-review

5 Citations (Scopus)

Abstract

The additional water from the Antarctic ice sheet and ice shelves due to climate-induced melt can impact ocean circulation and global climate. However, the major processes driving melt are not adequately represented in Coupled Model Intercomparison Project phase 6 (CMIP6) models. Here, we analyze a novel multi-model ensemble of CMIP6 models with consistent meltwater addition to examine the robustness of the modeled response to meltwater, which has not been possible in previous single-model studies. Antarctic meltwater addition induces a substantial weakening of open-ocean deep convection. Additionally, Antarctic Bottom Water warms, its volume contracts, and the sea surface cools. However, the magnitude of the reduction varies greatly across models, with differing anomalies correlated with their respective mean-state climatology, indicating the state-dependency of the climate response to meltwater. A better representation of the Southern Ocean mean state is necessary for narrowing the inter-model spread of response to Antarctic meltwater.

Original language	English
Article number	e2023GL106492
Number of pages	11
Journal	Geophysical Research Letters
Volume	50
Issue number	24
DOIs	https://doi.org/10.1029/2023GL106492
Publication status	Published - 28 Dec 2023

Keywords

Antarctic bottom water
Antarctic meltwater additions
climate models
deep convection
Southern Ocean

UN SDGs

This output contributes to the following UN Sustainable Development Goals (SDGs)

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10.1029/2023GL106492Licence: CC BY-NC-ND

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Chen, J. J., Swart, N. C., Beadling, R., Cheng, X., Hattermann, T., Jüling, A., Li, Q., Marshall, J., Martin, T., Muilwijk, M., Pauling, A. G., Purich, A., Smith, I. J., & Thomas, M. (2023). Reduced Deep Convection and Bottom Water Formation Due To Antarctic Meltwater in a Multi-Model Ensemble. Geophysical Research Letters, 50(24), Article e2023GL106492. https://doi.org/10.1029/2023GL106492

@article{6fb67fd2673d4256b2ccb1bf4b6e7854,

title = "Reduced Deep Convection and Bottom Water Formation Due To Antarctic Meltwater in a Multi-Model Ensemble",

abstract = "The additional water from the Antarctic ice sheet and ice shelves due to climate-induced melt can impact ocean circulation and global climate. However, the major processes driving melt are not adequately represented in Coupled Model Intercomparison Project phase 6 (CMIP6) models. Here, we analyze a novel multi-model ensemble of CMIP6 models with consistent meltwater addition to examine the robustness of the modeled response to meltwater, which has not been possible in previous single-model studies. Antarctic meltwater addition induces a substantial weakening of open-ocean deep convection. Additionally, Antarctic Bottom Water warms, its volume contracts, and the sea surface cools. However, the magnitude of the reduction varies greatly across models, with differing anomalies correlated with their respective mean-state climatology, indicating the state-dependency of the climate response to meltwater. A better representation of the Southern Ocean mean state is necessary for narrowing the inter-model spread of response to Antarctic meltwater.",

keywords = "Antarctic bottom water, Antarctic meltwater additions, climate models, deep convection, Southern Ocean",

author = "Chen, {Jia Jia} and Swart, {Neil C.} and Rebecca Beadling and Xuhua Cheng and Tore Hattermann and Andr{\'e} J{\"u}ling and Qian Li and John Marshall and Torge Martin and Morven Muilwijk and Pauling, {Andrew G.} and Ariaan Purich and Smith, {Inga J.} and Max Thomas",

note = "Funding Information: JJC and XHC acknowledge the support from the Natural Science Foundation of China (nos. 41876002). MM and TH were supported by funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 101003826 via project CRiceS. QL and JM were supported by the NASA MAP program 19-MAP19-0011 and the MIT-GISS cooperative agreement. The model simulations and analysis were conducted on the NASA High-End Computing (HEC) Program through the NASA Center for Climate Simulation (NCCS) at Goddard Space Flight Center. MT, AGP, and IJS were supported by the Deep South National Science Challenge (MBIE C01X1412) and the Antarctic Science Platform (University of Otago subcontract 19424 from VUW's ASP Project 4 contract with Antarctica New Zealand through MBIE SSIF Programmes Investment ANTA1801), and acknowledge use of high performance computing facilities, consulting support, and training services from New Zealand eScience Infrastructure (NeSI: funded by collaborator institutions and through MBIE's Research Infrastructure programme). AP was supported by the Australian Research Council Special Research Initiative for Securing Antarctica's Environmental Future (SR200100005). Funding Information: JJC and XHC acknowledge the support from the Natural Science Foundation of China (nos. 41876002). MM and TH were supported by funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 101003826 via project CRiceS. QL and JM were supported by the NASA MAP program 19‐MAP19‐0011 and the MIT‐GISS cooperative agreement. The model simulations and analysis were conducted on the NASA High‐End Computing (HEC) Program through the NASA Center for Climate Simulation (NCCS) at Goddard Space Flight Center. MT, AGP, and IJS were supported by the Deep South National Science Challenge (MBIE C01X1412) and the Antarctic Science Platform (University of Otago subcontract 19424 from VUW's ASP Project 4 contract with Antarctica New Zealand through MBIE SSIF Programmes Investment ANTA1801), and acknowledge use of high performance computing facilities, consulting support, and training services from New Zealand eScience Infrastructure (NeSI: funded by collaborator institutions and through MBIE's Research Infrastructure programme). AP was supported by the Australian Research Council Special Research Initiative for Securing Antarctica's Environmental Future (SR200100005). Publisher Copyright: {\textcopyright} 2023. The Authors.",

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Chen, JJ, Swart, NC, Beadling, R, Cheng, X, Hattermann, T, Jüling, A, Li, Q, Marshall, J, Martin, T, Muilwijk, M, Pauling, AG, Purich, A, Smith, IJ & Thomas, M 2023, 'Reduced Deep Convection and Bottom Water Formation Due To Antarctic Meltwater in a Multi-Model Ensemble', Geophysical Research Letters, vol. 50, no. 24, e2023GL106492. https://doi.org/10.1029/2023GL106492

TY - JOUR

T1 - Reduced Deep Convection and Bottom Water Formation Due To Antarctic Meltwater in a Multi-Model Ensemble

AU - Chen, Jia Jia

AU - Swart, Neil C.

AU - Beadling, Rebecca

AU - Cheng, Xuhua

AU - Hattermann, Tore

AU - Jüling, André

AU - Li, Qian

AU - Marshall, John

AU - Martin, Torge

AU - Muilwijk, Morven

AU - Pauling, Andrew G.

AU - Purich, Ariaan

AU - Smith, Inga J.

AU - Thomas, Max

N1 - Funding Information: JJC and XHC acknowledge the support from the Natural Science Foundation of China (nos. 41876002). MM and TH were supported by funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 101003826 via project CRiceS. QL and JM were supported by the NASA MAP program 19-MAP19-0011 and the MIT-GISS cooperative agreement. The model simulations and analysis were conducted on the NASA High-End Computing (HEC) Program through the NASA Center for Climate Simulation (NCCS) at Goddard Space Flight Center. MT, AGP, and IJS were supported by the Deep South National Science Challenge (MBIE C01X1412) and the Antarctic Science Platform (University of Otago subcontract 19424 from VUW's ASP Project 4 contract with Antarctica New Zealand through MBIE SSIF Programmes Investment ANTA1801), and acknowledge use of high performance computing facilities, consulting support, and training services from New Zealand eScience Infrastructure (NeSI: funded by collaborator institutions and through MBIE's Research Infrastructure programme). AP was supported by the Australian Research Council Special Research Initiative for Securing Antarctica's Environmental Future (SR200100005). Funding Information: JJC and XHC acknowledge the support from the Natural Science Foundation of China (nos. 41876002). MM and TH were supported by funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 101003826 via project CRiceS. QL and JM were supported by the NASA MAP program 19‐MAP19‐0011 and the MIT‐GISS cooperative agreement. The model simulations and analysis were conducted on the NASA High‐End Computing (HEC) Program through the NASA Center for Climate Simulation (NCCS) at Goddard Space Flight Center. MT, AGP, and IJS were supported by the Deep South National Science Challenge (MBIE C01X1412) and the Antarctic Science Platform (University of Otago subcontract 19424 from VUW's ASP Project 4 contract with Antarctica New Zealand through MBIE SSIF Programmes Investment ANTA1801), and acknowledge use of high performance computing facilities, consulting support, and training services from New Zealand eScience Infrastructure (NeSI: funded by collaborator institutions and through MBIE's Research Infrastructure programme). AP was supported by the Australian Research Council Special Research Initiative for Securing Antarctica's Environmental Future (SR200100005). Publisher Copyright: © 2023. The Authors.

PY - 2023/12/28

Y1 - 2023/12/28

N2 - The additional water from the Antarctic ice sheet and ice shelves due to climate-induced melt can impact ocean circulation and global climate. However, the major processes driving melt are not adequately represented in Coupled Model Intercomparison Project phase 6 (CMIP6) models. Here, we analyze a novel multi-model ensemble of CMIP6 models with consistent meltwater addition to examine the robustness of the modeled response to meltwater, which has not been possible in previous single-model studies. Antarctic meltwater addition induces a substantial weakening of open-ocean deep convection. Additionally, Antarctic Bottom Water warms, its volume contracts, and the sea surface cools. However, the magnitude of the reduction varies greatly across models, with differing anomalies correlated with their respective mean-state climatology, indicating the state-dependency of the climate response to meltwater. A better representation of the Southern Ocean mean state is necessary for narrowing the inter-model spread of response to Antarctic meltwater.

AB - The additional water from the Antarctic ice sheet and ice shelves due to climate-induced melt can impact ocean circulation and global climate. However, the major processes driving melt are not adequately represented in Coupled Model Intercomparison Project phase 6 (CMIP6) models. Here, we analyze a novel multi-model ensemble of CMIP6 models with consistent meltwater addition to examine the robustness of the modeled response to meltwater, which has not been possible in previous single-model studies. Antarctic meltwater addition induces a substantial weakening of open-ocean deep convection. Additionally, Antarctic Bottom Water warms, its volume contracts, and the sea surface cools. However, the magnitude of the reduction varies greatly across models, with differing anomalies correlated with their respective mean-state climatology, indicating the state-dependency of the climate response to meltwater. A better representation of the Southern Ocean mean state is necessary for narrowing the inter-model spread of response to Antarctic meltwater.

KW - Antarctic bottom water

KW - Antarctic meltwater additions

KW - climate models

KW - deep convection

KW - Southern Ocean

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U2 - 10.1029/2023GL106492

DO - 10.1029/2023GL106492

M3 - Article

AN - SCOPUS:85180239707

SN - 0094-8276

VL - 50

JO - Geophysical Research Letters

JF - Geophysical Research Letters

IS - 24

M1 - e2023GL106492

ER -

Reduced Deep Convection and Bottom Water Formation Due To Antarctic Meltwater in a Multi-Model Ensemble

Abstract

Keywords

UN SDGs

Access to Document

Other files and links

SAEF: Securing Antarctica’s Environmental Future – An Evidence-Based, Informatics Approach

Cite this

Reduced Deep Convection and Bottom Water Formation Due To Antarctic Meltwater in a Multi-Model Ensemble

Abstract

Keywords

UN SDGs

Access to Document

Other files and links

Projects

SAEF: Securing Antarctica’s Environmental Future – An Evidence-Based, Informatics Approach

Cite this