Ventilation of the Upper Oxygen Minimum Zone in the Coastal Region Off Mexico: Implications of El Niño 2015–2016
As a result of anthropogenic activities, it has been predicted that the ocean will be challenged with rising temperature, increased stratification, ocean acidification, stronger more frequent tropical storms, and oxygen depletion. In the tropical Pacific off central Mexico all these phenomena are al...
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ftdoajarticles:oai:doaj.org/article:237ff0b9607345b7b4f1357a39490604 2023-05-15T17:51:57+02:00 Ventilation of the Upper Oxygen Minimum Zone in the Coastal Region Off Mexico: Implications of El Niño 2015–2016 Pablo N. Trucco-Pignata José Martín Hernández-Ayón Eduardo Santamaria-del-Angel Emilio Beier Laura Sánchez-Velasco Victor M. Godínez Orión Norzagaray 2019-07-01T00:00:00Z https://doi.org/10.3389/fmars.2019.00459 https://doaj.org/article/237ff0b9607345b7b4f1357a39490604 EN eng Frontiers Media S.A. https://www.frontiersin.org/article/10.3389/fmars.2019.00459/full https://doaj.org/toc/2296-7745 2296-7745 doi:10.3389/fmars.2019.00459 https://doaj.org/article/237ff0b9607345b7b4f1357a39490604 Frontiers in Marine Science, Vol 6 (2019) oxygen minimum zones dissolved inorganic carbon El Niño 2015–2016 oxycline eastern tropical North Pacific Science Q General. Including nature conservation geographical distribution QH1-199.5 article 2019 ftdoajarticles https://doi.org/10.3389/fmars.2019.00459 2022-12-31T06:35:59Z As a result of anthropogenic activities, it has been predicted that the ocean will be challenged with rising temperature, increased stratification, ocean acidification, stronger more frequent tropical storms, and oxygen depletion. In the tropical Pacific off central Mexico all these phenomena are already occurring naturally, providing a laboratory from which to explore ocean biogeochemical dynamics that are predicted under future anthropogenic forcing conditions. Here, seasonally anomalous surface tropical waters were detected as a result of the developing “Godzilla El Niño 2015–2016.” The incursion of this oxygenated water modified the local structure of an intense and shallow oxygen minimum zone (OMZ), partially eroding and intensifying the oxycline while having an associated impact on the carbon maximum zone. The core of the OMZ (<4.4 μmol kg–1) was centered around 474 m, with a variant upper level between 50 and 360 m depth. Below the dominance of Tropical Surface Waters, the thickness of the oxycline varied between 10 and 325 m, with intensity values up to 11 μmol kg–1 m–1. The change in dissolved inorganic carbon (DIC) and apparent oxygen utilization yielded a molar ratio of δDIC = 0.98 × δAOU during June 2015 and of δDIC = 1.08 × δAOU for March 2016. A further decrease in the average content of DIC was observed in the carbon maximum zone for 2016. Traditionally, different explanations have been proposed to account for changing oxygen concentrations in the ocean rather than considering the interactions between multiple forcing factors. Our results highlight the significance of an episodic event like El Niño in the distribution and concentration of O2 and DIC and as a plausible mechanism of ventilation and increased oxygen availability in the upper OMZ of the tropical Pacific off central Mexico. Article in Journal/Newspaper Ocean acidification Directory of Open Access Journals: DOAJ Articles Pacific Frontiers in Marine Science 6 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
oxygen minimum zones dissolved inorganic carbon El Niño 2015–2016 oxycline eastern tropical North Pacific Science Q General. Including nature conservation geographical distribution QH1-199.5 |
spellingShingle |
oxygen minimum zones dissolved inorganic carbon El Niño 2015–2016 oxycline eastern tropical North Pacific Science Q General. Including nature conservation geographical distribution QH1-199.5 Pablo N. Trucco-Pignata José Martín Hernández-Ayón Eduardo Santamaria-del-Angel Emilio Beier Laura Sánchez-Velasco Victor M. Godínez Orión Norzagaray Ventilation of the Upper Oxygen Minimum Zone in the Coastal Region Off Mexico: Implications of El Niño 2015–2016 |
topic_facet |
oxygen minimum zones dissolved inorganic carbon El Niño 2015–2016 oxycline eastern tropical North Pacific Science Q General. Including nature conservation geographical distribution QH1-199.5 |
description |
As a result of anthropogenic activities, it has been predicted that the ocean will be challenged with rising temperature, increased stratification, ocean acidification, stronger more frequent tropical storms, and oxygen depletion. In the tropical Pacific off central Mexico all these phenomena are already occurring naturally, providing a laboratory from which to explore ocean biogeochemical dynamics that are predicted under future anthropogenic forcing conditions. Here, seasonally anomalous surface tropical waters were detected as a result of the developing “Godzilla El Niño 2015–2016.” The incursion of this oxygenated water modified the local structure of an intense and shallow oxygen minimum zone (OMZ), partially eroding and intensifying the oxycline while having an associated impact on the carbon maximum zone. The core of the OMZ (<4.4 μmol kg–1) was centered around 474 m, with a variant upper level between 50 and 360 m depth. Below the dominance of Tropical Surface Waters, the thickness of the oxycline varied between 10 and 325 m, with intensity values up to 11 μmol kg–1 m–1. The change in dissolved inorganic carbon (DIC) and apparent oxygen utilization yielded a molar ratio of δDIC = 0.98 × δAOU during June 2015 and of δDIC = 1.08 × δAOU for March 2016. A further decrease in the average content of DIC was observed in the carbon maximum zone for 2016. Traditionally, different explanations have been proposed to account for changing oxygen concentrations in the ocean rather than considering the interactions between multiple forcing factors. Our results highlight the significance of an episodic event like El Niño in the distribution and concentration of O2 and DIC and as a plausible mechanism of ventilation and increased oxygen availability in the upper OMZ of the tropical Pacific off central Mexico. |
format |
Article in Journal/Newspaper |
author |
Pablo N. Trucco-Pignata José Martín Hernández-Ayón Eduardo Santamaria-del-Angel Emilio Beier Laura Sánchez-Velasco Victor M. Godínez Orión Norzagaray |
author_facet |
Pablo N. Trucco-Pignata José Martín Hernández-Ayón Eduardo Santamaria-del-Angel Emilio Beier Laura Sánchez-Velasco Victor M. Godínez Orión Norzagaray |
author_sort |
Pablo N. Trucco-Pignata |
title |
Ventilation of the Upper Oxygen Minimum Zone in the Coastal Region Off Mexico: Implications of El Niño 2015–2016 |
title_short |
Ventilation of the Upper Oxygen Minimum Zone in the Coastal Region Off Mexico: Implications of El Niño 2015–2016 |
title_full |
Ventilation of the Upper Oxygen Minimum Zone in the Coastal Region Off Mexico: Implications of El Niño 2015–2016 |
title_fullStr |
Ventilation of the Upper Oxygen Minimum Zone in the Coastal Region Off Mexico: Implications of El Niño 2015–2016 |
title_full_unstemmed |
Ventilation of the Upper Oxygen Minimum Zone in the Coastal Region Off Mexico: Implications of El Niño 2015–2016 |
title_sort |
ventilation of the upper oxygen minimum zone in the coastal region off mexico: implications of el niño 2015–2016 |
publisher |
Frontiers Media S.A. |
publishDate |
2019 |
url |
https://doi.org/10.3389/fmars.2019.00459 https://doaj.org/article/237ff0b9607345b7b4f1357a39490604 |
geographic |
Pacific |
geographic_facet |
Pacific |
genre |
Ocean acidification |
genre_facet |
Ocean acidification |
op_source |
Frontiers in Marine Science, Vol 6 (2019) |
op_relation |
https://www.frontiersin.org/article/10.3389/fmars.2019.00459/full https://doaj.org/toc/2296-7745 2296-7745 doi:10.3389/fmars.2019.00459 https://doaj.org/article/237ff0b9607345b7b4f1357a39490604 |
op_doi |
https://doi.org/10.3389/fmars.2019.00459 |
container_title |
Frontiers in Marine Science |
container_volume |
6 |
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1766159250946523136 |