Simulations of glacial/interglacial cycles with simple box-models. The ocean CO2 source during deglaciations
Máster en Oceanografía Paillard and Parrenin [2004] model has been modified to obtain a closer fit to 18O and CO2 time-series for the last 800 kyr. Some sub-models have been developed, finding an improvement in performance if CO2 sensitivity to I65 insolation is eliminated, and if different response...
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ftunivlaspalmas:oai:https://accedacris.ulpgc.es:10553/10698 2023-05-15T13:44:42+02:00 Simulations of glacial/interglacial cycles with simple box-models. The ocean CO2 source during deglaciations Herrero i Navarro, Carmen Garcia-Olivares, Antonio Facultad de Ciencias del Mar 2013-09-11T05:00:10Z application/pdf http://hdl.handle.net/10553/10698 eng eng http://hdl.handle.net/10553/10698 687037 - by-nc-nd info:eu-repo/semantics/openAccess CC-BY-NC-ND 2510 Oceanografía info:eu-repo/semantics/masterThesis 2013 ftunivlaspalmas 2019-09-08T16:38:25Z Máster en Oceanografía Paillard and Parrenin [2004] model has been modified to obtain a closer fit to 18O and CO2 time-series for the last 800 kyr. Some sub-models have been developed, finding an improvement in performance if CO2 sensitivity to I65 insolation is eliminated, and if different response times are assumed for both absorption/emission of CO2 and for ablation/ accumulation of ice. Correlations between simulated and experimental time-series have increased from 0.64 and 0.61 (for ice volume and CO2) to 0.89 and 0.81, respectively. It has been found that the model is almost insensitive to late Austral summer insolation (60°S, 21st February) which leads to some conceptual changes, characterized in the Local Model with Double Stratification (LMDS). In LMDS, local proxies for Antarctic temperature have been used and stratification has been described to operate in two different ways: locally via the extent of Antarctic ice sheet and local temperature; and globally through global ice volume, V (which is strongly correlated to temperature changes in Northern Hemisphere), making a interconnection between oceanic pulse of CO2 in Southern Ocean (SO) and Northern Hemisphere (NH). According to this model, terminations are produced by I65 amplification, through CO2- T and T -CO2 feedback, in synergy with an extra CO2 contribution coming from the deep ocean. This CO2 pulse may be controlled by variations in the deep water formation rate in the Antarctic shelf, which is strongly dependent on ice volume and sea ice extent, being thus consistent with either a teleconnection mechanism via North Atlantic Deep Water upwelled in the SO (mechanism suggested by Gildor and Tziperman [2001]), or with sea-ice extent controlled by a local temperature (as suggested by Paillard and Parrenin [2004]). Master Thesis Antarc* Antarctic Ice Sheet North Atlantic Deep Water North Atlantic Sea ice Southern Ocean Universidad de Las Palmas de Gran Canaria: Acceda Antarctic Austral Southern Ocean The Antarctic |
institution |
Open Polar |
collection |
Universidad de Las Palmas de Gran Canaria: Acceda |
op_collection_id |
ftunivlaspalmas |
language |
English |
topic |
2510 Oceanografía |
spellingShingle |
2510 Oceanografía Herrero i Navarro, Carmen Simulations of glacial/interglacial cycles with simple box-models. The ocean CO2 source during deglaciations |
topic_facet |
2510 Oceanografía |
description |
Máster en Oceanografía Paillard and Parrenin [2004] model has been modified to obtain a closer fit to 18O and CO2 time-series for the last 800 kyr. Some sub-models have been developed, finding an improvement in performance if CO2 sensitivity to I65 insolation is eliminated, and if different response times are assumed for both absorption/emission of CO2 and for ablation/ accumulation of ice. Correlations between simulated and experimental time-series have increased from 0.64 and 0.61 (for ice volume and CO2) to 0.89 and 0.81, respectively. It has been found that the model is almost insensitive to late Austral summer insolation (60°S, 21st February) which leads to some conceptual changes, characterized in the Local Model with Double Stratification (LMDS). In LMDS, local proxies for Antarctic temperature have been used and stratification has been described to operate in two different ways: locally via the extent of Antarctic ice sheet and local temperature; and globally through global ice volume, V (which is strongly correlated to temperature changes in Northern Hemisphere), making a interconnection between oceanic pulse of CO2 in Southern Ocean (SO) and Northern Hemisphere (NH). According to this model, terminations are produced by I65 amplification, through CO2- T and T -CO2 feedback, in synergy with an extra CO2 contribution coming from the deep ocean. This CO2 pulse may be controlled by variations in the deep water formation rate in the Antarctic shelf, which is strongly dependent on ice volume and sea ice extent, being thus consistent with either a teleconnection mechanism via North Atlantic Deep Water upwelled in the SO (mechanism suggested by Gildor and Tziperman [2001]), or with sea-ice extent controlled by a local temperature (as suggested by Paillard and Parrenin [2004]). |
author2 |
Garcia-Olivares, Antonio Facultad de Ciencias del Mar |
format |
Master Thesis |
author |
Herrero i Navarro, Carmen |
author_facet |
Herrero i Navarro, Carmen |
author_sort |
Herrero i Navarro, Carmen |
title |
Simulations of glacial/interglacial cycles with simple box-models. The ocean CO2 source during deglaciations |
title_short |
Simulations of glacial/interglacial cycles with simple box-models. The ocean CO2 source during deglaciations |
title_full |
Simulations of glacial/interglacial cycles with simple box-models. The ocean CO2 source during deglaciations |
title_fullStr |
Simulations of glacial/interglacial cycles with simple box-models. The ocean CO2 source during deglaciations |
title_full_unstemmed |
Simulations of glacial/interglacial cycles with simple box-models. The ocean CO2 source during deglaciations |
title_sort |
simulations of glacial/interglacial cycles with simple box-models. the ocean co2 source during deglaciations |
publishDate |
2013 |
url |
http://hdl.handle.net/10553/10698 |
geographic |
Antarctic Austral Southern Ocean The Antarctic |
geographic_facet |
Antarctic Austral Southern Ocean The Antarctic |
genre |
Antarc* Antarctic Ice Sheet North Atlantic Deep Water North Atlantic Sea ice Southern Ocean |
genre_facet |
Antarc* Antarctic Ice Sheet North Atlantic Deep Water North Atlantic Sea ice Southern Ocean |
op_relation |
http://hdl.handle.net/10553/10698 687037 - |
op_rights |
by-nc-nd info:eu-repo/semantics/openAccess |
op_rightsnorm |
CC-BY-NC-ND |
_version_ |
1766205002412457984 |