Seawater softening of suture zones inhibits fracture propagation in Antarctic ice shelves

Bernd Kulessa; Adam D. Booth; Martin O’Leary; Daniel Mcgrath; Edward C. King; Adrian J. Luckman; Paul R. Holland; Daniela Jansen; Suzanne L. Bevan; Sarah S. Thompson; Bryn Hubbard

doi:10.1038/s41467-019-13539-x

Seawater softening of suture zones inhibits fracture propagation in Antarctic ice shelves

Bernd Kulessa, Adam D. Booth, Martin O’Leary, Daniel Mcgrath, Edward C. King, Adrian J. Luckman, Paul R. Holland, Daniela Jansen, Suzanne L. Bevan, Sarah S. Thompson, Bryn Hubbard

Adran Daearyddiaeth a Gwyddorau Daear

Allbwn ymchwil: Cyfraniad at gyfnodolyn › Erthygl › adolygiad gan gymheiriaid

13 Dyfyniadau (Scopus)

141 Wedi eu Llwytho i Lawr (Pure)

Crynodeb

Suture zones are abundant on Antarctic ice shelves and widely observed to impede fracture propagation, greatly enhancing ice-shelf stability. Using seismic and radar observations on the Larsen C Ice Shelf of the Antarctic Peninsula, we confirm that such zones are highly heterogeneous, consisting of multiple meteoric and marine ice bodies of diverse provenance fused together. Here we demonstrate that fracture detainment is predominantly controlled by enhanced seawater content in suture zones, rather than by enhanced temperature as previously thought. We show that interstitial seawater can reduce fracture-driving stress by orders of magnitude, promoting both viscous relaxation and the development of micro cracks, the incidence of which scales inversely with stress intensity. We show how simple analysis of viscous buckles in ice-penetrating radar data can quantify the seawater content of suture zones and their modification of the ice-shelf’s stress regime. By limiting fracture, enhancing stability and restraining continental ice discharge into the ocean, suture zones act as vital regulators of Antarctic mass balance

Iaith wreiddiol	Saesneg
Rhif yr erthygl	5491
Nifer y tudalennau	12
Cyfnodolyn	Nature Communications
Cyfrol	10
Rhif cyhoeddi	1
Dynodwyr Gwrthrych Digidol (DOIs)	https://doi.org/10.1038/s41467-019-13539-x
Statws	Cyhoeddwyd - 02 Rhag 2019

NDC y CU

Mae’r allbwn hwn yn cyfrannu at y Nod(au) Datblygu Cynaliadwy canlynol

Mynediad at Ddogfen

10.1038/s41467-019-13539-xTrwydded: CC BY

Seawater softening of suture zones inhibits fracture propagation in Antarctic ice shelvesFersiwn derfynol wedi’i chyhoeddi, 6.45 MBTrwydded: CC BY

Cysylltiad parhaol

Dolen barhaus

Ffeiliau eraill a chysylltiadau

Dolen i’r cyhoeddiad yn Scopus

Bryn Hubbard
- byhaber.acuk
- Adran Daearyddiaeth a Gwyddorau Daear - Professor
Unigolyn: Dysgu ac Ymchwil

1 Wedi Gorffen

MIDAS: Impact of surafec melt and ponding on ice shelf dynamics and stability
Hubbard, B. (Prif Ymchwilydd), Luckman, A. J. (Prif Ymchwilydd) & Kulessa, B. (Cyd-ymchwilydd)
Natural Environment Research Council
07 Ebr 2014 → 06 Ebr 2017
Prosiect: Ymchwil a ariannwyd yn allanol

Dyfynnu hyn

@article{7befffcb581c44e1b8d6bc70fd079982,

title = "Seawater softening of suture zones inhibits fracture propagation in Antarctic ice shelves",

abstract = "Suture zones are abundant on Antarctic ice shelves and widely observed to impede fracture propagation, greatly enhancing ice-shelf stability. Using seismic and radar observations on the Larsen C Ice Shelf of the Antarctic Peninsula, we confirm that such zones are highly heterogeneous, consisting of multiple meteoric and marine ice bodies of diverse provenance fused together. Here we demonstrate that fracture detainment is predominantly controlled by enhanced seawater content in suture zones, rather than by enhanced temperature as previously thought. We show that interstitial seawater can reduce fracture-driving stress by orders of magnitude, promoting both viscous relaxation and the development of micro cracks, the incidence of which scales inversely with stress intensity. We show how simple analysis of viscous buckles in ice-penetrating radar data can quantify the seawater content of suture zones and their modification of the ice-shelf{\textquoteright}s stress regime. By limiting fracture, enhancing stability and restraining continental ice discharge into the ocean, suture zones act as vital regulators of Antarctic mass balance",

author = "Bernd Kulessa and Booth, {Adam D.} and Martin O{\textquoteright}Leary and Daniel Mcgrath and King, {Edward C.} and Luckman, {Adrian J.} and Holland, {Paul R.} and Daniela Jansen and Bevan, {Suzanne L.} and Thompson, {Sarah S.} and Bryn Hubbard",

note = "Funding Information: B.K. and A.J.L. led NERC projects NE/E012914/1 (with D.J. as the postdoctoral scientist) and NE/L005409/1 (co-led by B.H. and including M.O.L. and S.L.B. as postdoctoral scientists) that made this work possible, and S.S.T. was funded by an AXA postdoctoral fellowship. B.K. developed the joined interpretation of all lines of evidence for which P.R.H. offered major critical review. B.K. also wrote the manuscript, processed the seismic data in Fig. 6a and created it along with Figs. 4 and 9. A.D.B. processed and analysed the seismic data in Figs. 6b, c, 7 and 8, which he also created. M.O.L. developed the viscous buckling analysis and created the data for Fig. 9, and D.M.G. conducted the flowline modelling and created Fig. 5. E.C.K. was a Co-Investigator on NE/E012914/1 and processed the GPR data for Fig. 4. S.L.B., S.S.T. and A.J.L. processed the satellite data underlying Figs. 1–3 and created them. B.H. guided physical interpretation of ice units. All co-authors critically reviewed the manuscript and contributed to its development. Funding Information: We acknowledge major support by UK Natural Environment Research Council (NERC) grants NE/E012914/1 and NE/L005409/1, Loan 863 of the NERC{\textquoteright}s Geophysical Equipment Facility, an AXA postdoctoral fellowship to SST and Michael Chester for assistance during the 2008/09 field campaign. We also thank the National Snow and Ice Data Center, Boulder, CO, USA, for the distribution of the satellite data underlying Fig. 2 and ESA for those underlying Fig. 3. Publisher Copyright: {\textcopyright} 2019, The Author(s).",

year = "2019",

month = dec,

day = "2",

doi = "10.1038/s41467-019-13539-x",

language = "English",

volume = "10",

journal = "Nature Communications",

issn = "2041-1723",

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TY - JOUR

T1 - Seawater softening of suture zones inhibits fracture propagation in Antarctic ice shelves

AU - Kulessa, Bernd

AU - Booth, Adam D.

AU - O’Leary, Martin

AU - Mcgrath, Daniel

AU - King, Edward C.

AU - Luckman, Adrian J.

AU - Holland, Paul R.

AU - Jansen, Daniela

AU - Bevan, Suzanne L.

AU - Thompson, Sarah S.

AU - Hubbard, Bryn

N1 - Funding Information: B.K. and A.J.L. led NERC projects NE/E012914/1 (with D.J. as the postdoctoral scientist) and NE/L005409/1 (co-led by B.H. and including M.O.L. and S.L.B. as postdoctoral scientists) that made this work possible, and S.S.T. was funded by an AXA postdoctoral fellowship. B.K. developed the joined interpretation of all lines of evidence for which P.R.H. offered major critical review. B.K. also wrote the manuscript, processed the seismic data in Fig. 6a and created it along with Figs. 4 and 9. A.D.B. processed and analysed the seismic data in Figs. 6b, c, 7 and 8, which he also created. M.O.L. developed the viscous buckling analysis and created the data for Fig. 9, and D.M.G. conducted the flowline modelling and created Fig. 5. E.C.K. was a Co-Investigator on NE/E012914/1 and processed the GPR data for Fig. 4. S.L.B., S.S.T. and A.J.L. processed the satellite data underlying Figs. 1–3 and created them. B.H. guided physical interpretation of ice units. All co-authors critically reviewed the manuscript and contributed to its development. Funding Information: We acknowledge major support by UK Natural Environment Research Council (NERC) grants NE/E012914/1 and NE/L005409/1, Loan 863 of the NERC’s Geophysical Equipment Facility, an AXA postdoctoral fellowship to SST and Michael Chester for assistance during the 2008/09 field campaign. We also thank the National Snow and Ice Data Center, Boulder, CO, USA, for the distribution of the satellite data underlying Fig. 2 and ESA for those underlying Fig. 3. Publisher Copyright: © 2019, The Author(s).

PY - 2019/12/2

Y1 - 2019/12/2

N2 - Suture zones are abundant on Antarctic ice shelves and widely observed to impede fracture propagation, greatly enhancing ice-shelf stability. Using seismic and radar observations on the Larsen C Ice Shelf of the Antarctic Peninsula, we confirm that such zones are highly heterogeneous, consisting of multiple meteoric and marine ice bodies of diverse provenance fused together. Here we demonstrate that fracture detainment is predominantly controlled by enhanced seawater content in suture zones, rather than by enhanced temperature as previously thought. We show that interstitial seawater can reduce fracture-driving stress by orders of magnitude, promoting both viscous relaxation and the development of micro cracks, the incidence of which scales inversely with stress intensity. We show how simple analysis of viscous buckles in ice-penetrating radar data can quantify the seawater content of suture zones and their modification of the ice-shelf’s stress regime. By limiting fracture, enhancing stability and restraining continental ice discharge into the ocean, suture zones act as vital regulators of Antarctic mass balance

AB - Suture zones are abundant on Antarctic ice shelves and widely observed to impede fracture propagation, greatly enhancing ice-shelf stability. Using seismic and radar observations on the Larsen C Ice Shelf of the Antarctic Peninsula, we confirm that such zones are highly heterogeneous, consisting of multiple meteoric and marine ice bodies of diverse provenance fused together. Here we demonstrate that fracture detainment is predominantly controlled by enhanced seawater content in suture zones, rather than by enhanced temperature as previously thought. We show that interstitial seawater can reduce fracture-driving stress by orders of magnitude, promoting both viscous relaxation and the development of micro cracks, the incidence of which scales inversely with stress intensity. We show how simple analysis of viscous buckles in ice-penetrating radar data can quantify the seawater content of suture zones and their modification of the ice-shelf’s stress regime. By limiting fracture, enhancing stability and restraining continental ice discharge into the ocean, suture zones act as vital regulators of Antarctic mass balance

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U2 - 10.1038/s41467-019-13539-x

DO - 10.1038/s41467-019-13539-x

M3 - Article

C2 - 31792201

SN - 2041-1723

VL - 10

JO - Nature Communications

JF - Nature Communications

IS - 1

M1 - 5491

ER -

Seawater softening of suture zones inhibits fracture propagation in Antarctic ice shelves

Crynodeb

NDC y CU

Mynediad at Ddogfen

Cysylltiad parhaol

Ffeiliau eraill a chysylltiadau

Ôl bys

Proffiliau

Bryn Hubbard

Prosiectau

MIDAS: Impact of surafec melt and ponding on ice shelf dynamics and stability

Dyfynnu hyn