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On Modelling and Physics of Ice-Age Ice Sheet-Sea Level-Solid Earth Interactionslevel-Solid Earth Interactions.

Record Type:	Electronic resources : Monograph/item
Title/Author:	On Modelling and Physics of Ice-Age Ice Sheet-Sea Level-Solid Earth Interactionslevel-Solid Earth Interactions./
Author:	Han, Kyeore Holly.
Description:	1 online resource (206 pages)
Notes:	Source: Dissertations Abstracts International, Volume: 83-10, Section: B.
Contained By:	Dissertations Abstracts International83-10B.
Subject:	Motivation. -
Online resource:	http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=29043392click for full text (PQDT)
ISBN:	9798209933014

On Modelling and Physics of Ice-Age Ice Sheet-Sea Level-Solid Earth Interactionslevel-Solid Earth Interactions.
Han, Kyeore Holly.

On Modelling and Physics of Ice-Age Ice Sheet-Sea Level-Solid Earth Interactionslevel-Solid Earth Interactions. - 1 online resource (206 pages)

Source: Dissertations Abstracts International, Volume: 83-10, Section: B.

Thesis (Ph.D.)--McGill University (Canada), 2021.

Includes bibliographical references

The retreat and advance of ice sheets perturb the Earth's solid surface, gravitational field and rotation, leading to spatially and temporally varying changes in the elevation of the ocean surface and solid Earth and hence sea level (glacial isostatic adjustment; GIA). Modelling studies have shown that sea-level changes associated with GIA in turn feed back onto ice sheets, confirming the coupled nature of ice sheets, the solid Earth and sea level. These interactions occur over a range of timescales (from decadal to multi-millennial and longer) and have important implications for ice sheet stability and sensitivity to climate changes in marine and terrestrial settings. Understanding the physics of these interactions through the Earth's glacial history is pertinent to interpreting ice-sheet and sealevel records from the past, understanding ongoing changes and projecting future climate changes.This thesis expands 1) the understanding of the history and physics of coupled ice-sheet and sea-level changes in the Northern Hemisphere over the last glacial cycle and 2) the computational capability of coupled ice-sheet - sea-level modelling. In the first study, I apply a sea-level model to simulate gravitationally consistent sea-level changes in North America associated with ice melting through the last deglaciation (21-6 thousand years ago). I separate the ice and water loading signals from periods during active deglaciation and post-deglaciation phases and show how these signals lead to a possible bias in interpreting geophysicalrecords used to constrain the viscosity underlying mantle in the Hudson Bay region. I also identify sites where the bias is minimized in the region.In the second study, I explore how deformation of the solid Earth and perturbations of the gravitational field impacted the evolution of ice sheets in the Northern Hemisphere during the last glacial cycle using a coupled ice-sheet - sealevel model. I demonstrate that solid Earth deformation enhances the dynamics of the Northern Hemispheric ice sheets, causing greater fluctuations of ice sheets in North America and Eurasia throughout the glacial cycle and that gravitational perturbations influence the stability of marine-based sectors of ice on decadal to centennial timescales.Finally, I develop a novel "time window" algorithm in a sea-level model to replace the classic algorithm of temporal discretization of the ice history in the model. This algorithm improves the computational eciency of the model and thus allows for capturing the short-term scale interactions between ice sheets, solid Earth and sea level within glacial-cycle scale simulations with a coupled ice sheet - sea level model. I apply the new algorithm to simulate ice-sheet and sea-level variations globally over the past two glacial cycles and the future retreat of the Antarctic Ice Sheet due to anthropogenic climate warming between 1950- 2500 AD. I show that using the time window algorithm reduces the total CPU calculation times by at least by 50% in both cases.Overall, I contribute to expanding the understanding of the interactions between GIA and ice sheets over broader spatiotemporal scales.

Electronic reproduction.
Ann Arbor, Mich. :
ProQuest,
2023

Mode of access: World Wide Web

ISBN: 9798209933014Subjects--Topical Terms:

532704
Motivation.
Index Terms--Genre/Form:

542853
Electronic books.

On Modelling and Physics of Ice-Age Ice Sheet-Sea Level-Solid Earth Interactionslevel-Solid Earth Interactions.
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100 1 $a Han, Kyeore Holly. $3 3694476
245 1 0 $a On Modelling and Physics of Ice-Age Ice Sheet-Sea Level-Solid Earth Interactionslevel-Solid Earth Interactions.
264 0 $c 2021
300 $a 1 online resource (206 pages)
336 $a text $b txt $2 rdacontent
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500 $a Source: Dissertations Abstracts International, Volume: 83-10, Section: B.
500 $a Advisor: Gomez, Natalya.
502 $a Thesis (Ph.D.)--McGill University (Canada), 2021.
504 $a Includes bibliographical references
520 $a The retreat and advance of ice sheets perturb the Earth's solid surface, gravitational field and rotation, leading to spatially and temporally varying changes in the elevation of the ocean surface and solid Earth and hence sea level (glacial isostatic adjustment; GIA). Modelling studies have shown that sea-level changes associated with GIA in turn feed back onto ice sheets, confirming the coupled nature of ice sheets, the solid Earth and sea level. These interactions occur over a range of timescales (from decadal to multi-millennial and longer) and have important implications for ice sheet stability and sensitivity to climate changes in marine and terrestrial settings. Understanding the physics of these interactions through the Earth's glacial history is pertinent to interpreting ice-sheet and sealevel records from the past, understanding ongoing changes and projecting future climate changes.This thesis expands 1) the understanding of the history and physics of coupled ice-sheet and sea-level changes in the Northern Hemisphere over the last glacial cycle and 2) the computational capability of coupled ice-sheet - sea-level modelling. In the first study, I apply a sea-level model to simulate gravitationally consistent sea-level changes in North America associated with ice melting through the last deglaciation (21-6 thousand years ago). I separate the ice and water loading signals from periods during active deglaciation and post-deglaciation phases and show how these signals lead to a possible bias in interpreting geophysicalrecords used to constrain the viscosity underlying mantle in the Hudson Bay region. I also identify sites where the bias is minimized in the region.In the second study, I explore how deformation of the solid Earth and perturbations of the gravitational field impacted the evolution of ice sheets in the Northern Hemisphere during the last glacial cycle using a coupled ice-sheet - sealevel model. I demonstrate that solid Earth deformation enhances the dynamics of the Northern Hemispheric ice sheets, causing greater fluctuations of ice sheets in North America and Eurasia throughout the glacial cycle and that gravitational perturbations influence the stability of marine-based sectors of ice on decadal to centennial timescales.Finally, I develop a novel "time window" algorithm in a sea-level model to replace the classic algorithm of temporal discretization of the ice history in the model. This algorithm improves the computational eciency of the model and thus allows for capturing the short-term scale interactions between ice sheets, solid Earth and sea level within glacial-cycle scale simulations with a coupled ice sheet - sea level model. I apply the new algorithm to simulate ice-sheet and sea-level variations globally over the past two glacial cycles and the future retreat of the Antarctic Ice Sheet due to anthropogenic climate warming between 1950- 2500 AD. I show that using the time window algorithm reduces the total CPU calculation times by at least by 50% in both cases.Overall, I contribute to expanding the understanding of the interactions between GIA and ice sheets over broader spatiotemporal scales.
520 $a Le recul et l'avance des calottes glaciaires perturbent la surface solide de la Terre, son champ gravitationnel et sa rotation, entrainant des changements spatiaux et temporels a l'elevation de la surface de l'ocean et de la Terre solide et donc au niveau de la mer (ajustement isostatique glacier; GIA). Des etudes de modelisation ont demontre que les changements du niveau de la mer associes au GIA se repercutent a leur tour sur les calottes glaciaires, confirmant la nature couplee des calottes glaciaires, de la Terre solide et du niveau de la mer. Ces interactions se produisent sur une gamme d'echelles de temps (de la decennie a plusieurs millenaires et plus) et ont des implications importantes pour la stabilite des calottes glaciaires et leur sensibilite aux changements climatiques dans les milieux marins et terrestres. La comprehension du charactere et de la physique de ces interactions a travers l'histoire glaciaire de la Terre est pertinente pour interpreter les enregistrements passees des calottes glaciaires et du niveau de la mer, comprendre les changements en cours (actuels) et projeter les changements climatiques futurs.Cette these elargit 1) la comprehension de l'histoire et de la physique des changements couples de la calotte glaciaire et du niveau de la mer dans l'hemisphere nord au cours du dernier cycle glacier et 2) la capacite informatique de la modelisation couplee de la calotte glaciaire et du niveau de la mer. Dans la premiere etude, j'applique un modele du niveau de la mer pour simuler les changements gravitationnels du niveau de la mer en Amerique du Nord associes a la fonte des glaces lors de la derniere deglaciation (il y a 21000 a 6000 avant le present). Je separe les signaux de charge de glace et d'eau des periodes pendant les phases de deglaciation active et de post-deglaciation et je demontre comment ces signaux menent a un biais possible dans l'interpretation des enregistrements geophysiques utilises pour contraindre la viscosite du manteau sous-jacent la region de la baie d'Hudson. J'identifie egalement les sites ou le biais est minimise dans la region.Dans la deuxieme etude, j'explore comment la deformation de la Terre solide et les perturbations du champ gravitationnel ont eu un impact sur l'evolution des calottes glaciaires dans l'hemisphere nord au cours du dernier cycle glaciaire en utilisant un modele couple calotte glaciaire-niveau de la mer. Je demontre que la deformation de la Terre solide ameliore la dynamique des calottes glaciaires de l'hemisphere Nord, provoquant de plus grandes fluctuations des calottes glaciaires en Amerique du Nord et en Eurasie tout au long du cycle glacier et que les perturbations gravitationnelles influencent la stabilite des secteurs de glace marins sur des echelles de temps decennales a centenaires.Enfin, je developpe un nouvel algorithme de «fenetre temporelle» dans un modele de niveau de la mer pour remplacer l'algorithme classique de discretisation temporelle de l'histoire des glaces dans le modele. Cet algorithme ameliore l'efficacite informatique du modele et permet ainsi de capturer les interactions a court terme entre les calottes glaciaires, la Terre solide et le niveau de la mer dans des simulations a l'echelle du cycle glaciaire avec un modele couple calotte glaciaire - niveau de la mer. Je applique le nouvel algorithme pour simuler les variations des calottes glaciaires et du niveau de la mer a l'echelle mondiale au cours des deux derniers cycles glaciers et pour simuler le futur retrait de la calotte glaciaire antarctique en raison du rechauffement climatique anthropique entre 1950 et 2500 CE. Je demontre que l'utilisation de l'algorithme de fenetre temporelle reduit le temps total de calcul du processeur d'au moins 50% dans les deux cas.Dans l'ensemble, a travers cette these, je contribue a elargir la comprehension des interactions entre le GIA et les calottes glaciaires a des echelles spatiales et temporelles plus larges qu'auparavant.
533 $a Electronic reproduction. $b Ann Arbor, Mich. : $c ProQuest, $d 2023
538 $a Mode of access: World Wide Web
650 4 $a Motivation. $3 532704
650 4 $a Physics. $3 516296
650 4 $a Collaboration. $3 3556296
650 4 $a Greenhouse gases. $3 797971
650 4 $a Topography. $3 3561794
650 4 $a Sea level. $3 544062
650 4 $a Ice sheets. $3 550729
650 4 $a Earth. $3 643955
650 4 $a Algorithms. $3 536374
650 4 $a Viscoelasticity. $3 718183
650 4 $a Radiation. $3 673904
650 4 $a Climate change. $2 bicssc $3 2079509
650 4 $a Computer science. $3 523869
650 4 $a Physical geography. $3 516662
655 7 $a Electronic books. $2 lcsh $3 542853
690 $a 0404
690 $a 0605
690 $a 0984
690 $a 0368
710 2 $a ProQuest Information and Learning Co. $3 783688
710 2 $a McGill University (Canada). $3 1018122
773 0 $t Dissertations Abstracts International $g 83-10B.
856 4 0 $u http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=29043392 $z click for full text (PQDT)