{"id":{"repo_id":"mit","oai_identifier":"oai:dspace.mit.edu:1721.1/108917"},"canonical_url":"https://search.dev.ndltd.org/etd/mit/oai:dspace.mit.edu:1721.1/108917","repository":{"repo_id":"mit","name":"MIT","base_url":"https://dspace.mit.edu/oai/request"},"display":{"title":"Insight into chemical, biological, and physical processes in coastal waters from dissolved oxygen and inert gas tracers","abstract":"In this thesis, I use coastal measurements of dissolved O₂ and inert gases to provide insight into the chemical, biological, and physical processes that impact the oceanic cycles of carbon and dissolved gases. Dissolved O₂ concentration and triple isotopic composition trace net and gross biological productivity. The saturation states of inert gases trace physical processes, such as air-water gas exchange, temperature change, and mixing, that affect all gases. First, I developed a field-deployable system that measures Ne, Ar, Kr, and Xe gas ratios in water. It has precision and accuracy of 1 % or better, enables near-continuous measurements, and has much lower cost compared to existing laboratory-based methods. The system will increase the scientific community's access to use dissolved noble gases as environmental tracers. Second, I measured O₂ and five noble gases during a cruise in Monterey Bay, California. I developed a vertical model and found that accurately parameterizing bubble-mediated gas exchange was necessary to accurately simulate the He and Ne measurements. I present the first comparison of multiple gas tracer, incubation, and sediment trap-based productivity estimates in the coastal ocean. Net community production estimated from ¹⁵NO₃⁻ uptake and 02 /Ar gave equivalent results at steady state. Underway O₂/Ar measurements revealed submesoscale variability that was not apparent from daily incubations. Third, I quantified productivity by O₂ mass balance and air-water gas exchange by dual tracer (³He/SF₆ ) release during ice melt in the Bras d'Or Lakes, a Canadian estuary. The gas transfer velocity at >90 % ice cover was 6 % of the rate for nearly ice-free conditions. Rates of volumetric gross primary production were similar when the estuary was completely ice-covered and ice-free, and the ecosystem was on average net autotrophic during ice melt and net heterotrophic following ice melt. I present a method for incorporating the isotopic composition of H₂O into the O₂ isotope-based productivity calculations, which increases the estimated gross primary production in this study by 46-97 %. In summary, I describe a new noble gas analysis system and apply O₂ and inert gas observations in new ways to study chemical, biological, and physical processes in coastal waters.","abstract_html":"In this thesis, I use coastal measurements of dissolved O₂ and inert gases to provide insight into the chemical, biological, and physical processes that impact the oceanic cycles of carbon and dissolved gases. Dissolved O₂ concentration and triple isotopic composition trace net and gross biological productivity. The saturation states of inert gases trace physical processes, such as air-water gas exchange, temperature change, and mixing, that affect all gases. First, I developed a field-deployable system that measures Ne, Ar, Kr, and Xe gas ratios in water. It has precision and accuracy of 1 % or better, enables near-continuous measurements, and has much lower cost compared to existing laboratory-based methods. The system will increase the scientific community's access to use dissolved noble gases as environmental tracers. Second, I measured O₂ and five noble gases during a cruise in Monterey Bay, California. I developed a vertical model and found that accurately parameterizing bubble-mediated gas exchange was necessary to accurately simulate the He and Ne measurements. I present the first comparison of multiple gas tracer, incubation, and sediment trap-based productivity estimates in the coastal ocean. Net community production estimated from ¹⁵NO₃⁻ uptake and 02 /Ar gave equivalent results at steady state. Underway O₂/Ar measurements revealed submesoscale variability that was not apparent from daily incubations. Third, I quantified productivity by O₂ mass balance and air-water gas exchange by dual tracer (³He/SF₆ ) release during ice melt in the Bras d'Or Lakes, a Canadian estuary. The gas transfer velocity at >90 % ice cover was 6 % of the rate for nearly ice-free conditions. Rates of volumetric gross primary production were similar when the estuary was completely ice-covered and ice-free, and the ecosystem was on average net autotrophic during ice melt and net heterotrophic following ice melt. I present a method for incorporating the isotopic composition of H₂O into the O₂ isotope-based productivity calculations, which increases the estimated gross primary production in this study by 46-97 %. In summary, I describe a new noble gas analysis system and apply O₂ and inert gas observations in new ways to study chemical, biological, and physical processes in coastal waters.","abstract_has_math":false,"creators":["Manning, Cara Charlotte Marie"],"institution":"Massachusetts Institute of Technology","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":"Joint Program in Oceanography/Applied Ocean Science and Engineering.","school":null,"contributors":[],"advisors":["Rachel H.R. Stanley and David P. Nicholson."],"committee_chairs":[],"committee_members":[],"year":2017,"date_issued":"2017","date_published":"2017","updated_at":"2026-07-22T22:20:59Z","subjects":["Joint Program in Oceanography/Applied Ocean Science and Engineering.","Earth, Atmospheric, and Planetary Sciences.","Woods Hole Oceanographic Institution."],"languages":["eng"],"rights":["MIT theses are protected by copyright. They may be viewed, downloaded, or printed from this source but further reproduction or distribution in any format is prohibited without written permission."],"rights_urls":["http://dspace.mit.edu/handle/1721.1/7582"],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/1721.1/108917","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Rachel H.R. Stanley and David P. 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Department of Earth, Atmospheric, and Planetary Sciences.","Woods Hole Oceanographic Institution."]},{"key":"dc:contributor.other","label":"Dc Contributor Other","values":["Woods Hole Oceanographic Institution."]},{"key":"dc:creator","label":"Author","values":["Manning, Cara Charlotte Marie"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2017-05-11T19:55:35Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2017-05-11T19:55:35Z"]},{"key":"dc:date.issued","label":"Date","values":["2017"]},{"key":"dc:publisher","label":"Institution","values":["Massachusetts Institute of Technology"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Joint Program in Oceanography/Applied Ocean Science and Engineering.","Earth, Atmospheric, and Planetary Sciences.","Woods Hole Oceanographic Institution."]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["eng"]},{"key":"dc:rights","label":"Dc Rights","values":["MIT theses are protected by copyright. They may be viewed, downloaded, or printed from this source but further reproduction or distribution in any format is prohibited without written permission."]},{"key":"dc:rights.uri","label":"Rights URI","values":["http://dspace.mit.edu/handle/1721.1/7582"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://hdl.handle.net/1721.1/108917"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Thesis: Ph. D., Joint Program in Oceanography/Applied Ocean Science and Engineering (Massachusetts Institute of Technology, Department of Earth, Atmospheric, and Planetary Sciences; and the Woods Hole Oceanographic Institution), 2017.","Cataloged from PDF version of thesis.","Includes bibliographical references (pages 185-213)."]},{"key":"dc:description.abstract","label":"Abstract","values":["In this thesis, I use coastal measurements of dissolved O₂ and inert gases to provide insight into the chemical, biological, and physical processes that impact the oceanic cycles of carbon and dissolved gases. Dissolved O₂ concentration and triple isotopic composition trace net and gross biological productivity. The saturation states of inert gases trace physical processes, such as air-water gas exchange, temperature change, and mixing, that affect all gases. First, I developed a field-deployable system that measures Ne, Ar, Kr, and Xe gas ratios in water. It has precision and accuracy of 1 % or better, enables near-continuous measurements, and has much lower cost compared to existing laboratory-based methods. The system will increase the scientific community's access to use dissolved noble gases as environmental tracers. Second, I measured O₂ and five noble gases during a cruise in Monterey Bay, California. I developed a vertical model and found that accurately parameterizing bubble-mediated gas exchange was necessary to accurately simulate the He and Ne measurements. I present the first comparison of multiple gas tracer, incubation, and sediment trap-based productivity estimates in the coastal ocean. Net community production estimated from ¹⁵NO₃⁻ uptake and 02 /Ar gave equivalent results at steady state. Underway O₂/Ar measurements revealed submesoscale variability that was not apparent from daily incubations. Third, I quantified productivity by O₂ mass balance and air-water gas exchange by dual tracer (³He/SF₆ ) release during ice melt in the Bras d'Or Lakes, a Canadian estuary. The gas transfer velocity at >90 % ice cover was 6 % of the rate for nearly ice-free conditions. Rates of volumetric gross primary production were similar when the estuary was completely ice-covered and ice-free, and the ecosystem was on average net autotrophic during ice melt and net heterotrophic following ice melt. I present a method for incorporating the isotopic composition of H₂O into the O₂ isotope-based productivity calculations, which increases the estimated gross primary production in this study by 46-97 %. In summary, I describe a new noble gas analysis system and apply O₂ and inert gas observations in new ways to study chemical, biological, and physical processes in coastal waters."]},{"key":"dc:description.degree","label":"Dc Description Degree","values":["Ph. D."]},{"key":"dc:title","label":"Title","values":["Insight into chemical, biological, and physical processes in coastal waters from dissolved oxygen and inert gas tracers"]}]}],"canonical_facts":{"dc:contributor.advisor":["Rachel H.R. Stanley and David P. Nicholson."],"dc:contributor.department":["Joint Program in Oceanography/Applied Ocean Science and Engineering.","Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences.","Woods Hole Oceanographic Institution."],"dc:contributor.other":["Woods Hole Oceanographic Institution."],"dc:creator":["Manning, Cara Charlotte Marie"],"dc:date.accessioned":["2017-05-11T19:55:35Z"],"dc:date.available":["2017-05-11T19:55:35Z"],"dc:date.issued":["2017"],"dc:description":["Thesis: Ph. D., Joint Program in Oceanography/Applied Ocean Science and Engineering (Massachusetts Institute of Technology, Department of Earth, Atmospheric, and Planetary Sciences; and the Woods Hole Oceanographic Institution), 2017.","Cataloged from PDF version of thesis.","Includes bibliographical references (pages 185-213)."],"dc:description.abstract":["In this thesis, I use coastal measurements of dissolved O₂ and inert gases to provide insight into the chemical, biological, and physical processes that impact the oceanic cycles of carbon and dissolved gases. Dissolved O₂ concentration and triple isotopic composition trace net and gross biological productivity. The saturation states of inert gases trace physical processes, such as air-water gas exchange, temperature change, and mixing, that affect all gases. First, I developed a field-deployable system that measures Ne, Ar, Kr, and Xe gas ratios in water. It has precision and accuracy of 1 % or better, enables near-continuous measurements, and has much lower cost compared to existing laboratory-based methods. The system will increase the scientific community's access to use dissolved noble gases as environmental tracers. Second, I measured O₂ and five noble gases during a cruise in Monterey Bay, California. I developed a vertical model and found that accurately parameterizing bubble-mediated gas exchange was necessary to accurately simulate the He and Ne measurements. I present the first comparison of multiple gas tracer, incubation, and sediment trap-based productivity estimates in the coastal ocean. Net community production estimated from ¹⁵NO₃⁻ uptake and 02 /Ar gave equivalent results at steady state. Underway O₂/Ar measurements revealed submesoscale variability that was not apparent from daily incubations. Third, I quantified productivity by O₂ mass balance and air-water gas exchange by dual tracer (³He/SF₆ ) release during ice melt in the Bras d'Or Lakes, a Canadian estuary. The gas transfer velocity at >90 % ice cover was 6 % of the rate for nearly ice-free conditions. Rates of volumetric gross primary production were similar when the estuary was completely ice-covered and ice-free, and the ecosystem was on average net autotrophic during ice melt and net heterotrophic following ice melt. I present a method for incorporating the isotopic composition of H₂O into the O₂ isotope-based productivity calculations, which increases the estimated gross primary production in this study by 46-97 %. In summary, I describe a new noble gas analysis system and apply O₂ and inert gas observations in new ways to study chemical, biological, and physical processes in coastal waters."],"dc:description.degree":["Ph. D."],"dc:identifier.uri":["http://hdl.handle.net/1721.1/108917"],"dc:language.iso":["eng"],"dc:publisher":["Massachusetts Institute of Technology"],"dc:rights":["MIT theses are protected by copyright. They may be viewed, downloaded, or printed from this source but further reproduction or distribution in any format is prohibited without written permission."],"dc:rights.uri":["http://dspace.mit.edu/handle/1721.1/7582"],"dc:subject":["Joint Program in Oceanography/Applied Ocean Science and Engineering.","Earth, Atmospheric, and Planetary Sciences.","Woods Hole Oceanographic Institution."],"dc:title":["Insight into chemical, biological, and physical processes in coastal waters from dissolved oxygen and inert gas tracers"],"dc:type":["Thesis"]},"updated_at":"2026-07-22T22:20:59Z"}