An Integrated Modeling Study of Ocean Circulation, the Ocean Carbon Cycle, Marine Ecosystems, and Climate Change
155 p. Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2006. The unifying theme of this study is to conduct an extensive exploration of various interactions between ocean circulation, the carbon cycle, marine ecosystems, and climate change using an earth system model of intermediate comp...
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ftunivillidea:oai:www.ideals.illinois.edu:2142/85970 2023-05-15T17:37:00+02:00 An Integrated Modeling Study of Ocean Circulation, the Ocean Carbon Cycle, Marine Ecosystems, and Climate Change Cao, Long Jain, Atul K. 2006 http://hdl.handle.net/2142/85970 unknown http://hdl.handle.net/2142/85970 (MiAaPQ)AAI3269853 Biogeochemistry text 2006 ftunivillidea 2016-03-19T23:51:51Z 155 p. Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2006. The unifying theme of this study is to conduct an extensive exploration of various interactions between ocean circulation, the carbon cycle, marine ecosystems, and climate change using an earth system model of intermediate complexity, ISAM-2.5D (Integrated Science Assessment Model). First, through the simulation of radiocarbon (in terms of Delta14C) it is demonstrated that the inclusion of isopycnal diffusion and a parameterization of eddy-induced circulation in the ISAM-2.5D model yields the most realistic representation of ocean mixing and circulation. Secondly, I demonstrate the value of the simulation of multiple tracers, combined with a variety of observational data, in constraining the ISAM-2.5D model that has been constrained by the simulation of Delta14C. Through the simulation of ocean biogeochemical cycles and CFC-11 and the use of the updated observational data of bomb radiocarbon, I improve the Delta14C-constrained ISAM-2.5D model's performance in simulating ocean circulation and air-sea gas exchange, as well as its credibility in predicting oceanic carbon uptake. Third, I use the ISAM-2.5D model to assess the efficiency of direct carbon injection into the deep ocean with the influence of climate change. It is shown that the consideration of climate change enhances the retention time of injected carbon into the Atlantic Ocean as a result of weakened North Atlantic overturning circulation in a warming climate. However, the climatic effect is insignificant on the efficiency of carbon injection into the Pacific and Indian Oceans. Finally, I quantify that increased atmospheric CO2 concentrations would be mainly responsible for future ocean acidification, including lowering in ocean pH and sea water saturation state with respect to carbonate minerals. The consideration of climate change produces a second-order modification to projected ocean acidification. Therefore, in addition to its radiative effects on climate change, increased atmospheric CO2 concentrations could pose a great threat to marine ecosystems through ocean acidification, which is largely independent of the magnitude of climate change. Overall, this study yields a number of valuable insights into different aspects of the coupled ocean circulation-marine ecosystems-carbon cycle system and contributes to advance our understanding of the ocean carbon cycle and marine chemistry in an environment of changing climate. Text North Atlantic Ocean acidification University of Illinois at Urbana-Champaign: IDEALS (Illinois Digital Environment for Access to Learning and Scholarship) Indian Pacific |
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University of Illinois at Urbana-Champaign: IDEALS (Illinois Digital Environment for Access to Learning and Scholarship) |
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ftunivillidea |
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unknown |
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Biogeochemistry |
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Biogeochemistry Cao, Long An Integrated Modeling Study of Ocean Circulation, the Ocean Carbon Cycle, Marine Ecosystems, and Climate Change |
topic_facet |
Biogeochemistry |
description |
155 p. Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2006. The unifying theme of this study is to conduct an extensive exploration of various interactions between ocean circulation, the carbon cycle, marine ecosystems, and climate change using an earth system model of intermediate complexity, ISAM-2.5D (Integrated Science Assessment Model). First, through the simulation of radiocarbon (in terms of Delta14C) it is demonstrated that the inclusion of isopycnal diffusion and a parameterization of eddy-induced circulation in the ISAM-2.5D model yields the most realistic representation of ocean mixing and circulation. Secondly, I demonstrate the value of the simulation of multiple tracers, combined with a variety of observational data, in constraining the ISAM-2.5D model that has been constrained by the simulation of Delta14C. Through the simulation of ocean biogeochemical cycles and CFC-11 and the use of the updated observational data of bomb radiocarbon, I improve the Delta14C-constrained ISAM-2.5D model's performance in simulating ocean circulation and air-sea gas exchange, as well as its credibility in predicting oceanic carbon uptake. Third, I use the ISAM-2.5D model to assess the efficiency of direct carbon injection into the deep ocean with the influence of climate change. It is shown that the consideration of climate change enhances the retention time of injected carbon into the Atlantic Ocean as a result of weakened North Atlantic overturning circulation in a warming climate. However, the climatic effect is insignificant on the efficiency of carbon injection into the Pacific and Indian Oceans. Finally, I quantify that increased atmospheric CO2 concentrations would be mainly responsible for future ocean acidification, including lowering in ocean pH and sea water saturation state with respect to carbonate minerals. The consideration of climate change produces a second-order modification to projected ocean acidification. Therefore, in addition to its radiative effects on climate change, increased atmospheric CO2 concentrations could pose a great threat to marine ecosystems through ocean acidification, which is largely independent of the magnitude of climate change. Overall, this study yields a number of valuable insights into different aspects of the coupled ocean circulation-marine ecosystems-carbon cycle system and contributes to advance our understanding of the ocean carbon cycle and marine chemistry in an environment of changing climate. |
author2 |
Jain, Atul K. |
format |
Text |
author |
Cao, Long |
author_facet |
Cao, Long |
author_sort |
Cao, Long |
title |
An Integrated Modeling Study of Ocean Circulation, the Ocean Carbon Cycle, Marine Ecosystems, and Climate Change |
title_short |
An Integrated Modeling Study of Ocean Circulation, the Ocean Carbon Cycle, Marine Ecosystems, and Climate Change |
title_full |
An Integrated Modeling Study of Ocean Circulation, the Ocean Carbon Cycle, Marine Ecosystems, and Climate Change |
title_fullStr |
An Integrated Modeling Study of Ocean Circulation, the Ocean Carbon Cycle, Marine Ecosystems, and Climate Change |
title_full_unstemmed |
An Integrated Modeling Study of Ocean Circulation, the Ocean Carbon Cycle, Marine Ecosystems, and Climate Change |
title_sort |
integrated modeling study of ocean circulation, the ocean carbon cycle, marine ecosystems, and climate change |
publishDate |
2006 |
url |
http://hdl.handle.net/2142/85970 |
geographic |
Indian Pacific |
geographic_facet |
Indian Pacific |
genre |
North Atlantic Ocean acidification |
genre_facet |
North Atlantic Ocean acidification |
op_relation |
http://hdl.handle.net/2142/85970 (MiAaPQ)AAI3269853 |
_version_ |
1766136691396968448 |