Glacial-cycle simulations of the Antarctic Ice Sheet with the Parallel Ice Sheet Model (PISM) – Part 1: Boundary conditions and climatic forcing
Simulations of the glacial–interglacial history of the Antarctic Ice Sheet provide insights into dynamic threshold behavior and estimates of the ice sheet's contributions to global sea-level changes for the past, present and future. However, boundary conditions are weakly constrained, in partic...
Published in: | The Cryosphere |
---|---|
Main Authors: | , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Copernicus Publications (EGU)
2020
|
Subjects: | |
Online Access: | https://oceanrep.geomar.de/id/eprint/54743/ https://oceanrep.geomar.de/id/eprint/54743/1/tc-14-599-2020.pdf https://doi.org/10.5194/tc-14-599-2020 |
id |
ftoceanrep:oai:oceanrep.geomar.de:54743 |
---|---|
record_format |
openpolar |
spelling |
ftoceanrep:oai:oceanrep.geomar.de:54743 2023-08-27T04:04:20+02:00 Glacial-cycle simulations of the Antarctic Ice Sheet with the Parallel Ice Sheet Model (PISM) – Part 1: Boundary conditions and climatic forcing Albrecht, Torsten Winkelmann, Ricarda Levermann, Anders 2020 text https://oceanrep.geomar.de/id/eprint/54743/ https://oceanrep.geomar.de/id/eprint/54743/1/tc-14-599-2020.pdf https://doi.org/10.5194/tc-14-599-2020 en eng Copernicus Publications (EGU) https://oceanrep.geomar.de/id/eprint/54743/1/tc-14-599-2020.pdf Albrecht, T. , Winkelmann, R. and Levermann, A. (2020) Glacial-cycle simulations of the Antarctic Ice Sheet with the Parallel Ice Sheet Model (PISM) – Part 1: Boundary conditions and climatic forcing. Open Access The Cryosphere, 14 (2). pp. 599-632. DOI 10.5194/tc-14-599-2020 <https://doi.org/10.5194/tc-14-599-2020>. doi:10.5194/tc-14-599-2020 cc_by_4.0 info:eu-repo/semantics/openAccess Article PeerReviewed 2020 ftoceanrep https://doi.org/10.5194/tc-14-599-2020 2023-08-06T23:19:54Z Simulations of the glacial–interglacial history of the Antarctic Ice Sheet provide insights into dynamic threshold behavior and estimates of the ice sheet's contributions to global sea-level changes for the past, present and future. However, boundary conditions are weakly constrained, in particular at the interface of the ice sheet and the bedrock. Also climatic forcing covering the last glacial cycles is uncertain, as it is based on sparse proxy data. We use the Parallel Ice Sheet Model (PISM) to investigate the dynamic effects of different choices of input data, e.g., for modern basal heat flux or reconstructions of past changes of sea level and surface temperature. As computational resources are limited, glacial-cycle simulations are performed using a comparably coarse model grid of 16 km and various parameterizations, e.g., for basal sliding, iceberg calving, or for past variations in precipitation and ocean temperatures. In this study we evaluate the model's transient sensitivity to corresponding parameter choices and to different boundary conditions over the last two glacial cycles and provide estimates of involved uncertainties. We also discuss isolated and combined effects of climate and sea-level forcing. Hence, this study serves as a “cookbook” for the growing community of PISM users and paleo-ice sheet modelers in general. For each of the different model uncertainties with regard to climatic forcing, ice and Earth dynamics, and basal processes, we select one representative model parameter that captures relevant uncertainties and motivates corresponding parameter ranges that bound the observed ice volume at present. The four selected parameters are systematically varied in a parameter ensemble analysis, which is described in a companion paper. Article in Journal/Newspaper Antarc* Antarctic Ice Sheet Iceberg* The Cryosphere OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) Antarctic The Antarctic The Cryosphere 14 2 599 632 |
institution |
Open Polar |
collection |
OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) |
op_collection_id |
ftoceanrep |
language |
English |
description |
Simulations of the glacial–interglacial history of the Antarctic Ice Sheet provide insights into dynamic threshold behavior and estimates of the ice sheet's contributions to global sea-level changes for the past, present and future. However, boundary conditions are weakly constrained, in particular at the interface of the ice sheet and the bedrock. Also climatic forcing covering the last glacial cycles is uncertain, as it is based on sparse proxy data. We use the Parallel Ice Sheet Model (PISM) to investigate the dynamic effects of different choices of input data, e.g., for modern basal heat flux or reconstructions of past changes of sea level and surface temperature. As computational resources are limited, glacial-cycle simulations are performed using a comparably coarse model grid of 16 km and various parameterizations, e.g., for basal sliding, iceberg calving, or for past variations in precipitation and ocean temperatures. In this study we evaluate the model's transient sensitivity to corresponding parameter choices and to different boundary conditions over the last two glacial cycles and provide estimates of involved uncertainties. We also discuss isolated and combined effects of climate and sea-level forcing. Hence, this study serves as a “cookbook” for the growing community of PISM users and paleo-ice sheet modelers in general. For each of the different model uncertainties with regard to climatic forcing, ice and Earth dynamics, and basal processes, we select one representative model parameter that captures relevant uncertainties and motivates corresponding parameter ranges that bound the observed ice volume at present. The four selected parameters are systematically varied in a parameter ensemble analysis, which is described in a companion paper. |
format |
Article in Journal/Newspaper |
author |
Albrecht, Torsten Winkelmann, Ricarda Levermann, Anders |
spellingShingle |
Albrecht, Torsten Winkelmann, Ricarda Levermann, Anders Glacial-cycle simulations of the Antarctic Ice Sheet with the Parallel Ice Sheet Model (PISM) – Part 1: Boundary conditions and climatic forcing |
author_facet |
Albrecht, Torsten Winkelmann, Ricarda Levermann, Anders |
author_sort |
Albrecht, Torsten |
title |
Glacial-cycle simulations of the Antarctic Ice Sheet with the Parallel Ice Sheet Model (PISM) – Part 1: Boundary conditions and climatic forcing |
title_short |
Glacial-cycle simulations of the Antarctic Ice Sheet with the Parallel Ice Sheet Model (PISM) – Part 1: Boundary conditions and climatic forcing |
title_full |
Glacial-cycle simulations of the Antarctic Ice Sheet with the Parallel Ice Sheet Model (PISM) – Part 1: Boundary conditions and climatic forcing |
title_fullStr |
Glacial-cycle simulations of the Antarctic Ice Sheet with the Parallel Ice Sheet Model (PISM) – Part 1: Boundary conditions and climatic forcing |
title_full_unstemmed |
Glacial-cycle simulations of the Antarctic Ice Sheet with the Parallel Ice Sheet Model (PISM) – Part 1: Boundary conditions and climatic forcing |
title_sort |
glacial-cycle simulations of the antarctic ice sheet with the parallel ice sheet model (pism) – part 1: boundary conditions and climatic forcing |
publisher |
Copernicus Publications (EGU) |
publishDate |
2020 |
url |
https://oceanrep.geomar.de/id/eprint/54743/ https://oceanrep.geomar.de/id/eprint/54743/1/tc-14-599-2020.pdf https://doi.org/10.5194/tc-14-599-2020 |
geographic |
Antarctic The Antarctic |
geographic_facet |
Antarctic The Antarctic |
genre |
Antarc* Antarctic Ice Sheet Iceberg* The Cryosphere |
genre_facet |
Antarc* Antarctic Ice Sheet Iceberg* The Cryosphere |
op_relation |
https://oceanrep.geomar.de/id/eprint/54743/1/tc-14-599-2020.pdf Albrecht, T. , Winkelmann, R. and Levermann, A. (2020) Glacial-cycle simulations of the Antarctic Ice Sheet with the Parallel Ice Sheet Model (PISM) – Part 1: Boundary conditions and climatic forcing. Open Access The Cryosphere, 14 (2). pp. 599-632. DOI 10.5194/tc-14-599-2020 <https://doi.org/10.5194/tc-14-599-2020>. doi:10.5194/tc-14-599-2020 |
op_rights |
cc_by_4.0 info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.5194/tc-14-599-2020 |
container_title |
The Cryosphere |
container_volume |
14 |
container_issue |
2 |
container_start_page |
599 |
op_container_end_page |
632 |
_version_ |
1775350669552648192 |