Variación espacial de la composición isotópica ó13C del carbono inorgánico disuelto en la región de aguas profundas del Golfo de México
This study provides new data to understand the carbon biogeochemical baseline in thedeep Gulf of Mexico waters (GM) based on the carbon isotopes of dissolved inorganiccarbon. Water samples from 40 deep-water stations south of 25°N were collected duringXIXIMI-II cruise, July 2011, aboard BO/Justo Sie...
| Autor: | |
|---|---|
| Tipo de recurso: | tesis de maestría |
| Estado: | Versión publicada |
| Fecha de publicación: | 2015 |
| País: | México |
| Institución: | Centro de Investigación Científica y de Educación Superior de Ensenada |
| Repositorio: | Repositorio Institucional CICESE |
| Idioma: | español |
| OAI Identifier: | oai:cicese.repositorioinstitucional.mx:1007/709 |
| Acceso en línea: | http://cicese.repositorioinstitucional.mx/jspui/handle/1007/709 |
| Access Level: | acceso abierto |
| Palabra clave: | info:eu-repo/classification/Autor/Carbono info:eu-repo/classification/cti/6 info:eu-repo/classification/cti/31 info:eu-repo/classification/cti/3105 |
| Sumario: | This study provides new data to understand the carbon biogeochemical baseline in thedeep Gulf of Mexico waters (GM) based on the carbon isotopes of dissolved inorganiccarbon. Water samples from 40 deep-water stations south of 25°N were collected duringXIXIMI-II cruise, July 2011, aboard BO/Justo Sierra while vertical continuous profiles oftemperature, salinity and dissolved oxygen [O<sub>2</sub>] were further measured in each station.We determined the carbon isotopic composition of the dissolved inorganic carbon (DIC)(δ<sup>13</sup>C<sub>DIC</sub>) at the Stable Isotopes Laboratory at CICESE. In contrast to what is reported inother parts of the ocean, the depth where the lighter δ<sup>13</sup>C<sub>DIC</sub> values are observed doesnot coincide with the depth of maximum apparent oxygen consumption (AOU) in the GMdeep-water region. Remarkably, density, oxygen and δ<sup>13</sup>C<sub>DIC</sub> depth profiles showedclear differences between the Loop current and the interior of the GM south of 25°N.We found the following averages δ<sup>13</sup>C<sub>DIC</sub> values in the Loop current and in the interior ofthe Gulf respectively: Surface Water: 1.23±0.08‰ and 1.01±0.09‰, SubtropicalUnderwater (SUW): 0.70±0.1‰, Gulf Common Water (GCW): 0.80±0.04‰, 18 degreewater (18°): 0.76±0.08‰ and 0.58±0.03‰, North Atlantic Central Water (NACW):0.79±0.02‰ and 0.67±0.03‰, South Atlantic Central Water (SACW): 0.83± 0.03‰ and0.77±0.04‰, Antarctic intermediate Water (AAIW): 0.97±0.1‰ and 0.92±0.03‰, NorthAtlantic Deep Water: 1.04±0.03‰ and 1.03±0.04‰. We observe the maximum O2consumption and the maximum d<sup>13</sup>C<sub>DIC</sub> depletion in the 18° water mass inside the GM, awater mass for which we derived the maximum oxygen consumption rates inside theGM. The following δ<sup>13</sup>C<sub>DIC</sub> preformed values where calculated: SUW: 1.19±0.11‰,GCW: 1.16±0.09‰, 18°:1.54±0.07‰, NACW: 1.99±0.05‰, SACW: 2.21±0.12‰, AAIW:2.36±0.15‰ y NADW: 2.07.±0.10. Maxima in δ<sup>13</sup>C<sub>DIC</sub> depletion from organic carbonremineralization are observed in the AAIW implying the longest residence time betweenthe site of formation and the GM. The 18° water shows the lightest δ<sup>13</sup>C<sub>DIC</sub> values in theGM implying the increasing importance of anthropogenic CO<sub>2</sub> injection at the site of thiswater mass formation in the North Atlantic during winter. |
|---|