Decadal-scale sensitivity of Northeast Greenland ice flow to errors in surface mass balance using ISSM
The behavior of the Greenland Ice Sheet, which is considered a major contributor to sea level changes, is best understood on century and longer time scales. However, on decadal time scales, its response is less predictable due to the difficulty of modeling surface climate, as well as incomplete unde...
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ftcdlib:qt87g5r9kc 2023-05-15T15:11:41+02:00 Decadal-scale sensitivity of Northeast Greenland ice flow to errors in surface mass balance using ISSM Schlegel, N-J. Larour, E. Seroussi, H. Morlighem, M. Box, J. E 667 - 680 2013-06-01 application/pdf http://www.escholarship.org/uc/item/87g5r9kc english eng eScholarship, University of California qt87g5r9kc http://www.escholarship.org/uc/item/87g5r9kc Attribution (CC BY): http://creativecommons.org/licenses/by/3.0/ CC-BY Schlegel, N-J.; Larour, E.; Seroussi, H.; Morlighem, M.; & Box, J. E. (2013). Decadal-scale sensitivity of Northeast Greenland ice flow to errors in surface mass balance using ISSM. Journal of Geophysical Research: Earth Surface, 118(2), 667 - 680. doi:10.1002/jgrf.20062. UC Irvine: Department of Earth System Science, UCI. Retrieved from: http://www.escholarship.org/uc/item/87g5r9kc Physical Sciences and Mathematics Greenland ice dynamics ice flow ice stream sensitivity surface mass balance climate forcing decadal variation error analysis mass balance sea level change sensitivity analysis spatial resolution Arctic Greenland Ice Sheet article 2013 ftcdlib https://doi.org/10.1002/jgrf.20062 2016-04-02T19:06:58Z The behavior of the Greenland Ice Sheet, which is considered a major contributor to sea level changes, is best understood on century and longer time scales. However, on decadal time scales, its response is less predictable due to the difficulty of modeling surface climate, as well as incomplete understanding of the dynamic processes responsible for ice flow. Therefore, it is imperative to understand how modeling advancements, such as increased spatial resolution or more comprehensive ice flow equations, might improve projections of ice sheet response to climatic trends. Here we examine how a finely resolved climate forcing influences a high-resolution ice stream model that considers longitudinal stresses. We simulate ice flow using a two-dimensional Shelfy-Stream Approximation implemented within the Ice Sheet System Model (ISSM) and use uncertainty quantification tools embedded within the model to calculate the sensitivity of ice flow within the Northeast Greenland Ice Stream to errors in surface mass balance (SMB) forcing. Our results suggest that the model tends to smooth ice velocities even when forced with extreme errors in SMB. Indeed, errors propagate linearly through the model, resulting in discharge uncertainty of 16% or 1.9 Gt/yr. We find that mass flux is most sensitive to local errors but is also affected by errors hundreds of kilometers away; thus, an accurate SMB map of the entire basin is critical for realistic simulation. Furthermore, sensitivity analyses indicate that SMB forcing needs to be provided at a resolution of at least 40 km. Article in Journal/Newspaper Arctic Greenland Ice Sheet University of California: eScholarship Arctic Greenland Journal of Geophysical Research: Earth Surface 118 2 667 680 |
institution |
Open Polar |
collection |
University of California: eScholarship |
op_collection_id |
ftcdlib |
language |
English |
topic |
Physical Sciences and Mathematics Greenland ice dynamics ice flow ice stream sensitivity surface mass balance climate forcing decadal variation error analysis mass balance sea level change sensitivity analysis spatial resolution Arctic Greenland Ice Sheet |
spellingShingle |
Physical Sciences and Mathematics Greenland ice dynamics ice flow ice stream sensitivity surface mass balance climate forcing decadal variation error analysis mass balance sea level change sensitivity analysis spatial resolution Arctic Greenland Ice Sheet Schlegel, N-J. Larour, E. Seroussi, H. Morlighem, M. Box, J. E Decadal-scale sensitivity of Northeast Greenland ice flow to errors in surface mass balance using ISSM |
topic_facet |
Physical Sciences and Mathematics Greenland ice dynamics ice flow ice stream sensitivity surface mass balance climate forcing decadal variation error analysis mass balance sea level change sensitivity analysis spatial resolution Arctic Greenland Ice Sheet |
description |
The behavior of the Greenland Ice Sheet, which is considered a major contributor to sea level changes, is best understood on century and longer time scales. However, on decadal time scales, its response is less predictable due to the difficulty of modeling surface climate, as well as incomplete understanding of the dynamic processes responsible for ice flow. Therefore, it is imperative to understand how modeling advancements, such as increased spatial resolution or more comprehensive ice flow equations, might improve projections of ice sheet response to climatic trends. Here we examine how a finely resolved climate forcing influences a high-resolution ice stream model that considers longitudinal stresses. We simulate ice flow using a two-dimensional Shelfy-Stream Approximation implemented within the Ice Sheet System Model (ISSM) and use uncertainty quantification tools embedded within the model to calculate the sensitivity of ice flow within the Northeast Greenland Ice Stream to errors in surface mass balance (SMB) forcing. Our results suggest that the model tends to smooth ice velocities even when forced with extreme errors in SMB. Indeed, errors propagate linearly through the model, resulting in discharge uncertainty of 16% or 1.9 Gt/yr. We find that mass flux is most sensitive to local errors but is also affected by errors hundreds of kilometers away; thus, an accurate SMB map of the entire basin is critical for realistic simulation. Furthermore, sensitivity analyses indicate that SMB forcing needs to be provided at a resolution of at least 40 km. |
format |
Article in Journal/Newspaper |
author |
Schlegel, N-J. Larour, E. Seroussi, H. Morlighem, M. Box, J. E |
author_facet |
Schlegel, N-J. Larour, E. Seroussi, H. Morlighem, M. Box, J. E |
author_sort |
Schlegel, N-J. |
title |
Decadal-scale sensitivity of Northeast Greenland ice flow to errors in surface mass balance using ISSM |
title_short |
Decadal-scale sensitivity of Northeast Greenland ice flow to errors in surface mass balance using ISSM |
title_full |
Decadal-scale sensitivity of Northeast Greenland ice flow to errors in surface mass balance using ISSM |
title_fullStr |
Decadal-scale sensitivity of Northeast Greenland ice flow to errors in surface mass balance using ISSM |
title_full_unstemmed |
Decadal-scale sensitivity of Northeast Greenland ice flow to errors in surface mass balance using ISSM |
title_sort |
decadal-scale sensitivity of northeast greenland ice flow to errors in surface mass balance using issm |
publisher |
eScholarship, University of California |
publishDate |
2013 |
url |
http://www.escholarship.org/uc/item/87g5r9kc |
op_coverage |
667 - 680 |
geographic |
Arctic Greenland |
geographic_facet |
Arctic Greenland |
genre |
Arctic Greenland Ice Sheet |
genre_facet |
Arctic Greenland Ice Sheet |
op_source |
Schlegel, N-J.; Larour, E.; Seroussi, H.; Morlighem, M.; & Box, J. E. (2013). Decadal-scale sensitivity of Northeast Greenland ice flow to errors in surface mass balance using ISSM. Journal of Geophysical Research: Earth Surface, 118(2), 667 - 680. doi:10.1002/jgrf.20062. UC Irvine: Department of Earth System Science, UCI. Retrieved from: http://www.escholarship.org/uc/item/87g5r9kc |
op_relation |
qt87g5r9kc http://www.escholarship.org/uc/item/87g5r9kc |
op_rights |
Attribution (CC BY): http://creativecommons.org/licenses/by/3.0/ |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.1002/jgrf.20062 |
container_title |
Journal of Geophysical Research: Earth Surface |
container_volume |
118 |
container_issue |
2 |
container_start_page |
667 |
op_container_end_page |
680 |
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1766342512054632448 |