Projecting Antarctica's contribution to future sea level rise from basal ice shelf melt using linear response functions of 16 ice sheet models (LARMIP-2)
<p>The sea level contribution of the Antarctic ice sheet constitutes a large uncertainty in future sea level projections. Here we apply a linear response theory approach to 16 state-of-the-art ice sheet models to estimate the Antarctic ice sheet contribution from basal ice shelf melting within...
Main Authors: | , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , |
---|---|
Format: | Article |
Language: | English |
Published: |
Copernicus Publications
2020-02-01
|
Series: | Earth System Dynamics |
Online Access: | https://www.earth-syst-dynam.net/11/35/2020/esd-11-35-2020.pdf |
id |
doaj-e6a747b9aaaf40f680e90273a5d96cc4 |
---|---|
record_format |
Article |
collection |
DOAJ |
language |
English |
format |
Article |
sources |
DOAJ |
author |
A. Levermann A. Levermann A. Levermann R. Winkelmann R. Winkelmann T. Albrecht H. Goelzer H. Goelzer N. R. Golledge N. R. Golledge R. Greve P. Huybrechts J. Jordan G. Leguy D. Martin M. Morlighem F. Pattyn D. Pollard A. Quiquet C. Rodehacke C. Rodehacke H. Seroussi J. Sutter J. Sutter T. Zhang J. Van Breedam R. Calov R. DeConto C. Dumas J. Garbe J. Garbe G. H. Gudmundsson M. J. Hoffman A. Humbert A. Humbert T. Kleiner W. H. Lipscomb M. Meinshausen M. Meinshausen E. Ng S. M. J. Nowicki M. Perego S. F. Price F. Saito N.-J. Schlegel S. Sun R. S. W. van de Wal R. S. W. van de Wal |
spellingShingle |
A. Levermann A. Levermann A. Levermann R. Winkelmann R. Winkelmann T. Albrecht H. Goelzer H. Goelzer N. R. Golledge N. R. Golledge R. Greve P. Huybrechts J. Jordan G. Leguy D. Martin M. Morlighem F. Pattyn D. Pollard A. Quiquet C. Rodehacke C. Rodehacke H. Seroussi J. Sutter J. Sutter T. Zhang J. Van Breedam R. Calov R. DeConto C. Dumas J. Garbe J. Garbe G. H. Gudmundsson M. J. Hoffman A. Humbert A. Humbert T. Kleiner W. H. Lipscomb M. Meinshausen M. Meinshausen E. Ng S. M. J. Nowicki M. Perego S. F. Price F. Saito N.-J. Schlegel S. Sun R. S. W. van de Wal R. S. W. van de Wal Projecting Antarctica's contribution to future sea level rise from basal ice shelf melt using linear response functions of 16 ice sheet models (LARMIP-2) Earth System Dynamics |
author_facet |
A. Levermann A. Levermann A. Levermann R. Winkelmann R. Winkelmann T. Albrecht H. Goelzer H. Goelzer N. R. Golledge N. R. Golledge R. Greve P. Huybrechts J. Jordan G. Leguy D. Martin M. Morlighem F. Pattyn D. Pollard A. Quiquet C. Rodehacke C. Rodehacke H. Seroussi J. Sutter J. Sutter T. Zhang J. Van Breedam R. Calov R. DeConto C. Dumas J. Garbe J. Garbe G. H. Gudmundsson M. J. Hoffman A. Humbert A. Humbert T. Kleiner W. H. Lipscomb M. Meinshausen M. Meinshausen E. Ng S. M. J. Nowicki M. Perego S. F. Price F. Saito N.-J. Schlegel S. Sun R. S. W. van de Wal R. S. W. van de Wal |
author_sort |
A. Levermann |
title |
Projecting Antarctica's contribution to future sea level rise from basal ice shelf melt using linear response functions of 16 ice sheet models (LARMIP-2) |
title_short |
Projecting Antarctica's contribution to future sea level rise from basal ice shelf melt using linear response functions of 16 ice sheet models (LARMIP-2) |
title_full |
Projecting Antarctica's contribution to future sea level rise from basal ice shelf melt using linear response functions of 16 ice sheet models (LARMIP-2) |
title_fullStr |
Projecting Antarctica's contribution to future sea level rise from basal ice shelf melt using linear response functions of 16 ice sheet models (LARMIP-2) |
title_full_unstemmed |
Projecting Antarctica's contribution to future sea level rise from basal ice shelf melt using linear response functions of 16 ice sheet models (LARMIP-2) |
title_sort |
projecting antarctica's contribution to future sea level rise from basal ice shelf melt using linear response functions of 16 ice sheet models (larmip-2) |
publisher |
Copernicus Publications |
series |
Earth System Dynamics |
issn |
2190-4979 2190-4987 |
publishDate |
2020-02-01 |
description |
<p>The sea level contribution of the Antarctic ice sheet
constitutes a large uncertainty in future sea level projections. Here we
apply a linear response theory approach to 16 state-of-the-art ice sheet
models to estimate the Antarctic ice sheet contribution from basal ice shelf
melting within the 21st century. The purpose of this computation is to
estimate the uncertainty of Antarctica's future contribution to global sea
level rise that arises from large uncertainty in the oceanic forcing and the
associated ice shelf melting. Ice shelf melting is considered to be a major
if not the largest perturbation of the ice sheet's flow into the ocean.
However, by computing only the sea level contribution in response to ice
shelf melting, our study is neglecting a number of processes such as
surface-mass-balance-related contributions. In assuming linear response
theory, we are able to capture complex temporal responses of the ice sheets,
but we neglect any self-dampening or self-amplifying processes. This is
particularly relevant in situations in which an instability is dominating the
ice loss. The results obtained here are thus relevant, in particular wherever the
ice loss is dominated by the forcing as opposed to an internal instability,
for example in strong ocean warming scenarios. In order to allow for
comparison the methodology was chosen to be exactly the same as in an
earlier study (Levermann
et al., 2014) but with 16 instead of 5 ice sheet models. We include
uncertainty in the atmospheric warming response to carbon emissions (full
range of CMIP5 climate model sensitivities), uncertainty in the oceanic
transport to the Southern Ocean (obtained from the time-delayed and scaled
oceanic subsurface warming in CMIP5 models in relation to the global mean
surface warming), and the observed range of responses of basal ice shelf
melting to oceanic warming outside the ice shelf cavity. This uncertainty in
basal ice shelf melting is then convoluted with the linear response
functions of each of the 16 ice sheet models to obtain the ice flow response
to the individual global warming path. The model median for the
observational period from 1992 to 2017 of the ice loss due to basal ice
shelf melting is 10.2 mm, with a likely range between 5.2 and 21.3 mm. For
the same period the Antarctic ice sheet lost mass equivalent to 7.4 mm of
global sea level rise, with a standard deviation of 3.7 mm (Shepherd et al., 2018) including all processes,
especially surface-mass-balance changes. For the unabated warming path,
Representative Concentration Pathway 8.5 (RCP8.5), we obtain a median contribution of the Antarctic ice sheet to
global mean sea level rise from basal ice shelf melting within the 21st
century of 17 cm, with a likely range (66th percentile around the mean) between
9 and 36 cm and a very likely range (90th percentile around the mean)
between 6 and 58 cm. For the RCP2.6 warming path, which will keep the
global mean temperature below <span class="inline-formula">2</span> <span class="inline-formula"><sup>∘</sup></span>C of global warming and is thus
consistent with the Paris Climate Agreement, the procedure yields a median of
13 cm of global mean sea level contribution. The likely range for the
RCP2.6 scenario is between 7 and 24 cm, and the very likely range is
between 4 and 37 cm. The structural uncertainties in the method do not
allow for an interpretation of any higher uncertainty percentiles. We provide
projections for the five Antarctic regions and for each model and each
scenario separately. The rate of sea level contribution is highest under
the RCP8.5 scenario. The maximum within the 21st century of the median
value is 4 cm per decade, with a likely range between 2 and 9 cm per decade
and a very likely range between 1 and 14 cm per decade.</p> |
url |
https://www.earth-syst-dynam.net/11/35/2020/esd-11-35-2020.pdf |
work_keys_str_mv |
AT alevermann projectingantarcticascontributiontofuturesealevelrisefrombasaliceshelfmeltusinglinearresponsefunctionsof16icesheetmodelslarmip2 AT alevermann projectingantarcticascontributiontofuturesealevelrisefrombasaliceshelfmeltusinglinearresponsefunctionsof16icesheetmodelslarmip2 AT alevermann projectingantarcticascontributiontofuturesealevelrisefrombasaliceshelfmeltusinglinearresponsefunctionsof16icesheetmodelslarmip2 AT rwinkelmann projectingantarcticascontributiontofuturesealevelrisefrombasaliceshelfmeltusinglinearresponsefunctionsof16icesheetmodelslarmip2 AT rwinkelmann projectingantarcticascontributiontofuturesealevelrisefrombasaliceshelfmeltusinglinearresponsefunctionsof16icesheetmodelslarmip2 AT talbrecht projectingantarcticascontributiontofuturesealevelrisefrombasaliceshelfmeltusinglinearresponsefunctionsof16icesheetmodelslarmip2 AT hgoelzer projectingantarcticascontributiontofuturesealevelrisefrombasaliceshelfmeltusinglinearresponsefunctionsof16icesheetmodelslarmip2 AT hgoelzer projectingantarcticascontributiontofuturesealevelrisefrombasaliceshelfmeltusinglinearresponsefunctionsof16icesheetmodelslarmip2 AT nrgolledge projectingantarcticascontributiontofuturesealevelrisefrombasaliceshelfmeltusinglinearresponsefunctionsof16icesheetmodelslarmip2 AT nrgolledge projectingantarcticascontributiontofuturesealevelrisefrombasaliceshelfmeltusinglinearresponsefunctionsof16icesheetmodelslarmip2 AT rgreve projectingantarcticascontributiontofuturesealevelrisefrombasaliceshelfmeltusinglinearresponsefunctionsof16icesheetmodelslarmip2 AT phuybrechts projectingantarcticascontributiontofuturesealevelrisefrombasaliceshelfmeltusinglinearresponsefunctionsof16icesheetmodelslarmip2 AT jjordan projectingantarcticascontributiontofuturesealevelrisefrombasaliceshelfmeltusinglinearresponsefunctionsof16icesheetmodelslarmip2 AT gleguy projectingantarcticascontributiontofuturesealevelrisefrombasaliceshelfmeltusinglinearresponsefunctionsof16icesheetmodelslarmip2 AT dmartin projectingantarcticascontributiontofuturesealevelrisefrombasaliceshelfmeltusinglinearresponsefunctionsof16icesheetmodelslarmip2 AT mmorlighem projectingantarcticascontributiontofuturesealevelrisefrombasaliceshelfmeltusinglinearresponsefunctionsof16icesheetmodelslarmip2 AT fpattyn projectingantarcticascontributiontofuturesealevelrisefrombasaliceshelfmeltusinglinearresponsefunctionsof16icesheetmodelslarmip2 AT dpollard projectingantarcticascontributiontofuturesealevelrisefrombasaliceshelfmeltusinglinearresponsefunctionsof16icesheetmodelslarmip2 AT aquiquet projectingantarcticascontributiontofuturesealevelrisefrombasaliceshelfmeltusinglinearresponsefunctionsof16icesheetmodelslarmip2 AT crodehacke projectingantarcticascontributiontofuturesealevelrisefrombasaliceshelfmeltusinglinearresponsefunctionsof16icesheetmodelslarmip2 AT crodehacke projectingantarcticascontributiontofuturesealevelrisefrombasaliceshelfmeltusinglinearresponsefunctionsof16icesheetmodelslarmip2 AT hseroussi projectingantarcticascontributiontofuturesealevelrisefrombasaliceshelfmeltusinglinearresponsefunctionsof16icesheetmodelslarmip2 AT jsutter projectingantarcticascontributiontofuturesealevelrisefrombasaliceshelfmeltusinglinearresponsefunctionsof16icesheetmodelslarmip2 AT jsutter projectingantarcticascontributiontofuturesealevelrisefrombasaliceshelfmeltusinglinearresponsefunctionsof16icesheetmodelslarmip2 AT tzhang projectingantarcticascontributiontofuturesealevelrisefrombasaliceshelfmeltusinglinearresponsefunctionsof16icesheetmodelslarmip2 AT jvanbreedam projectingantarcticascontributiontofuturesealevelrisefrombasaliceshelfmeltusinglinearresponsefunctionsof16icesheetmodelslarmip2 AT rcalov projectingantarcticascontributiontofuturesealevelrisefrombasaliceshelfmeltusinglinearresponsefunctionsof16icesheetmodelslarmip2 AT rdeconto projectingantarcticascontributiontofuturesealevelrisefrombasaliceshelfmeltusinglinearresponsefunctionsof16icesheetmodelslarmip2 AT cdumas projectingantarcticascontributiontofuturesealevelrisefrombasaliceshelfmeltusinglinearresponsefunctionsof16icesheetmodelslarmip2 AT jgarbe projectingantarcticascontributiontofuturesealevelrisefrombasaliceshelfmeltusinglinearresponsefunctionsof16icesheetmodelslarmip2 AT jgarbe projectingantarcticascontributiontofuturesealevelrisefrombasaliceshelfmeltusinglinearresponsefunctionsof16icesheetmodelslarmip2 AT ghgudmundsson projectingantarcticascontributiontofuturesealevelrisefrombasaliceshelfmeltusinglinearresponsefunctionsof16icesheetmodelslarmip2 AT mjhoffman projectingantarcticascontributiontofuturesealevelrisefrombasaliceshelfmeltusinglinearresponsefunctionsof16icesheetmodelslarmip2 AT ahumbert projectingantarcticascontributiontofuturesealevelrisefrombasaliceshelfmeltusinglinearresponsefunctionsof16icesheetmodelslarmip2 AT ahumbert projectingantarcticascontributiontofuturesealevelrisefrombasaliceshelfmeltusinglinearresponsefunctionsof16icesheetmodelslarmip2 AT tkleiner projectingantarcticascontributiontofuturesealevelrisefrombasaliceshelfmeltusinglinearresponsefunctionsof16icesheetmodelslarmip2 AT whlipscomb projectingantarcticascontributiontofuturesealevelrisefrombasaliceshelfmeltusinglinearresponsefunctionsof16icesheetmodelslarmip2 AT mmeinshausen projectingantarcticascontributiontofuturesealevelrisefrombasaliceshelfmeltusinglinearresponsefunctionsof16icesheetmodelslarmip2 AT mmeinshausen projectingantarcticascontributiontofuturesealevelrisefrombasaliceshelfmeltusinglinearresponsefunctionsof16icesheetmodelslarmip2 AT eng projectingantarcticascontributiontofuturesealevelrisefrombasaliceshelfmeltusinglinearresponsefunctionsof16icesheetmodelslarmip2 AT smjnowicki projectingantarcticascontributiontofuturesealevelrisefrombasaliceshelfmeltusinglinearresponsefunctionsof16icesheetmodelslarmip2 AT mperego projectingantarcticascontributiontofuturesealevelrisefrombasaliceshelfmeltusinglinearresponsefunctionsof16icesheetmodelslarmip2 AT sfprice projectingantarcticascontributiontofuturesealevelrisefrombasaliceshelfmeltusinglinearresponsefunctionsof16icesheetmodelslarmip2 AT fsaito projectingantarcticascontributiontofuturesealevelrisefrombasaliceshelfmeltusinglinearresponsefunctionsof16icesheetmodelslarmip2 AT njschlegel projectingantarcticascontributiontofuturesealevelrisefrombasaliceshelfmeltusinglinearresponsefunctionsof16icesheetmodelslarmip2 AT ssun projectingantarcticascontributiontofuturesealevelrisefrombasaliceshelfmeltusinglinearresponsefunctionsof16icesheetmodelslarmip2 AT rswvandewal projectingantarcticascontributiontofuturesealevelrisefrombasaliceshelfmeltusinglinearresponsefunctionsof16icesheetmodelslarmip2 AT rswvandewal projectingantarcticascontributiontofuturesealevelrisefrombasaliceshelfmeltusinglinearresponsefunctionsof16icesheetmodelslarmip2 |
_version_ |
1724848644751884288 |
spelling |
doaj-e6a747b9aaaf40f680e90273a5d96cc42020-11-25T02:26:12ZengCopernicus PublicationsEarth System Dynamics2190-49792190-49872020-02-0111357610.5194/esd-11-35-2020Projecting Antarctica's contribution to future sea level rise from basal ice shelf melt using linear response functions of 16 ice sheet models (LARMIP-2)A. Levermann0A. Levermann1A. Levermann2R. Winkelmann3R. Winkelmann4T. Albrecht5H. Goelzer6H. Goelzer7N. R. Golledge8N. R. Golledge9R. Greve10P. Huybrechts11J. Jordan12G. Leguy13D. Martin14M. Morlighem15F. Pattyn16D. Pollard17A. Quiquet18C. Rodehacke19C. Rodehacke20H. Seroussi21J. Sutter22J. Sutter23T. Zhang24J. Van Breedam25R. Calov26R. DeConto27C. Dumas28J. Garbe29J. Garbe30G. H. Gudmundsson31M. J. Hoffman32A. Humbert33A. Humbert34T. Kleiner35W. H. Lipscomb36M. Meinshausen37M. Meinshausen38E. Ng39S. M. J. Nowicki40M. Perego41S. F. Price42F. Saito43N.-J. Schlegel44S. Sun45R. S. W. van de Wal46R. S. W. van de Wal47Potsdam Institute for Climate Impact Research, Potsdam, GermanyLDEO, Columbia University, New York, USAInstitute of Physics and Astronomy, University of Potsdam, 14476 Potsdam, GermanyPotsdam Institute for Climate Impact Research, Potsdam, GermanyInstitute of Physics and Astronomy, University of Potsdam, 14476 Potsdam, GermanyPotsdam Institute for Climate Impact Research, Potsdam, GermanyInstitute for Marine and Atmospheric research Utrecht, Utrecht University, Utrecht, the NetherlandsLaboratoire de Glaciologie, Université libre de Bruxelles (ULB), Brussels, BelgiumAntarctic Research Centre, Victoria University of Wellington, Wellington 6140, New ZealandGNS Science, Avalon, Lower Hutt 5011, New ZealandInstitute of Low Temperature Science, Hokkaido University, Sapporo 060-0819, JapanEarth System Science & Departement Geografie, Vrije Universiteit Brussel, Brussels, BelgiumDepartment of Geography and Environmental Sciences, University of Northumbria, Newcastle, UKClimate and Global Dynamics Laboratory, National Center for Atmospheric Research, Boulder, CO, USALawrence Berkeley National Laboratory, Berkeley, CA, USADepartment of Earth System Science, University of California Irvine, Irvine, CA, USALaboratoire de Glaciologie, Université libre de Bruxelles (ULB), Brussels, BelgiumEarth and Environmental Systems Institute, Pennsylvania State University, University Park, Pennsylvania, USALaboratoire des Sciences du Climat et de l'Environnement, CEA/CNRS-INSU/UVSQ, Gif-sur-Yvette CEDEX, FranceDanish Meteorological Institute, Arctic and Climate, Copenhagen, DenmarkAlfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Bremerhaven, GermanyJet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USAAlfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Bremerhaven, GermanyPhysics Institute, University of Bern, Bern, SwitzerlandTheoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USAEarth System Science & Departement Geografie, Vrije Universiteit Brussel, Brussels, BelgiumPotsdam Institute for Climate Impact Research, Potsdam, GermanyDepartment of Geosciences, University of Massachusetts, Amherst, Massachusetts, USALaboratoire des Sciences du Climat et de l'Environnement, CEA/CNRS-INSU/UVSQ, Gif-sur-Yvette CEDEX, FrancePotsdam Institute for Climate Impact Research, Potsdam, GermanyInstitute of Physics and Astronomy, University of Potsdam, 14476 Potsdam, GermanyDepartment of Geography and Environmental Sciences, University of Northumbria, Newcastle, UKTheoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USAAlfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Bremerhaven, GermanyDepartment of Geosciences, University of Bremen, Bremen, GermanyAlfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Bremerhaven, GermanyClimate and Global Dynamics Laboratory, National Center for Atmospheric Research, Boulder, CO, USAPotsdam Institute for Climate Impact Research, Potsdam, GermanyClimate & Energy College, School of Earth Sciences, University of Melbourne, Parkville, Victoria, AustraliaLawrence Berkeley National Laboratory, Berkeley, CA, USANASA Goddard Space Flight Center, Greenbelt, MD, USACenter for Computing Research, Sandia National Laboratories, Albuquerque, New Mexico 87185, USATheoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USAJapan Agency for Marine-Earth Science and Technology, Yokohama, JapanJet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USALaboratoire de Glaciologie, Université libre de Bruxelles (ULB), Brussels, BelgiumInstitute for Marine and Atmospheric research Utrecht, Utrecht University, Utrecht, the NetherlandsGeosciences, Physical Geography, Utrecht University, Utrecht, the Netherlands<p>The sea level contribution of the Antarctic ice sheet constitutes a large uncertainty in future sea level projections. Here we apply a linear response theory approach to 16 state-of-the-art ice sheet models to estimate the Antarctic ice sheet contribution from basal ice shelf melting within the 21st century. The purpose of this computation is to estimate the uncertainty of Antarctica's future contribution to global sea level rise that arises from large uncertainty in the oceanic forcing and the associated ice shelf melting. Ice shelf melting is considered to be a major if not the largest perturbation of the ice sheet's flow into the ocean. However, by computing only the sea level contribution in response to ice shelf melting, our study is neglecting a number of processes such as surface-mass-balance-related contributions. In assuming linear response theory, we are able to capture complex temporal responses of the ice sheets, but we neglect any self-dampening or self-amplifying processes. This is particularly relevant in situations in which an instability is dominating the ice loss. The results obtained here are thus relevant, in particular wherever the ice loss is dominated by the forcing as opposed to an internal instability, for example in strong ocean warming scenarios. In order to allow for comparison the methodology was chosen to be exactly the same as in an earlier study (Levermann et al., 2014) but with 16 instead of 5 ice sheet models. We include uncertainty in the atmospheric warming response to carbon emissions (full range of CMIP5 climate model sensitivities), uncertainty in the oceanic transport to the Southern Ocean (obtained from the time-delayed and scaled oceanic subsurface warming in CMIP5 models in relation to the global mean surface warming), and the observed range of responses of basal ice shelf melting to oceanic warming outside the ice shelf cavity. This uncertainty in basal ice shelf melting is then convoluted with the linear response functions of each of the 16 ice sheet models to obtain the ice flow response to the individual global warming path. The model median for the observational period from 1992 to 2017 of the ice loss due to basal ice shelf melting is 10.2 mm, with a likely range between 5.2 and 21.3 mm. For the same period the Antarctic ice sheet lost mass equivalent to 7.4 mm of global sea level rise, with a standard deviation of 3.7 mm (Shepherd et al., 2018) including all processes, especially surface-mass-balance changes. For the unabated warming path, Representative Concentration Pathway 8.5 (RCP8.5), we obtain a median contribution of the Antarctic ice sheet to global mean sea level rise from basal ice shelf melting within the 21st century of 17 cm, with a likely range (66th percentile around the mean) between 9 and 36 cm and a very likely range (90th percentile around the mean) between 6 and 58 cm. For the RCP2.6 warming path, which will keep the global mean temperature below <span class="inline-formula">2</span> <span class="inline-formula"><sup>∘</sup></span>C of global warming and is thus consistent with the Paris Climate Agreement, the procedure yields a median of 13 cm of global mean sea level contribution. The likely range for the RCP2.6 scenario is between 7 and 24 cm, and the very likely range is between 4 and 37 cm. The structural uncertainties in the method do not allow for an interpretation of any higher uncertainty percentiles. We provide projections for the five Antarctic regions and for each model and each scenario separately. The rate of sea level contribution is highest under the RCP8.5 scenario. The maximum within the 21st century of the median value is 4 cm per decade, with a likely range between 2 and 9 cm per decade and a very likely range between 1 and 14 cm per decade.</p>https://www.earth-syst-dynam.net/11/35/2020/esd-11-35-2020.pdf |