Pliocene foraminifera and SST changes in ODP Site 184-1125

Fuente: PANGAEA
Guardado en:
Detalles Bibliográficos
Autores principales: Sabaa, Ashwaq T, Sikes, Elisabeth L, Hayward, Bruce William, Howard, William R
Formato: Dataset Open Access
Lenguaje:en
Publicado: PANGAEA 2004
Materias:
Acceso en línea:
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
_version_ 1867168554423418880
author Sabaa, Ashwaq T
Sikes, Elisabeth L
Hayward, Bruce William
Howard, William R
author_facet Sabaa, Ashwaq T
Sikes, Elisabeth L
Hayward, Bruce William
Howard, William R
collection Datos científicos de ciencias marinas y ambientales
contents Planktonic foraminiferal census counts were converted to sea surface temperature (SST) estimates using the modern analogue technique (MAT) for the middle-late Pliocene (4.0-2.37 Ma) in ODP Site 1125, north side of Chatham Rise, SW Pacific Ocean. MAT SST(warm) records range between 8°C and 20.5°C, and MAT SST(cold) records parallel that pattern but with a temperature range of 5-15°C. The modern position of Site 1125 is just north of the Subtropical Front and has an annual temperature range of ~14-18°C. Pliocene warmest temperatures are 1-2° warmer than modern summers, whereas cold season SST records are up to 6-10°C cooler than modern winters. Overall average temperatures at the site are 2-3°C cooler than modern temperatures during a time of sustained global warmth. Three major cold excursions centred on 3.35, 3.0, and 2.8 Ma showed warm season temperatures over 5°C colder than the last glacial maximum, experiencing temperatures typical of modern subantarctic waters. Two minor cold excursions at 2.7 Ma and 2.4 Ma experienced temperatures cooler than modern winters but not as cold as last glacial conditions. Cold season SSTs show a shift to warmer climate upward through the study interval, whereas warm season estimates remain essentially unchanged. We interpret the strong regional cooling of subtropical Southwest Pacific water through the middle-late Pliocene as having been caused by increased upwelling. It is also possible that the subtropical frontal zone moved north over the site in the Pliocene, however, this is considered the least likely interpretation. Our record of cool conditions in the Southwest Pacific corroborate evidence of cooler than modern conditions in other regions of the western Pacific through the mid-Pliocene despite overall global warming.
format Dataset Open Access
id pangaea_https___doi_org_10_1594_PANGAEA_734790
institution PANGAEA
language en
publishDate 2004
publisher PANGAEA
record_format pangaea
spellingShingle Pliocene foraminifera and SST changes in ODP Site 184-1125
Sabaa, Ashwaq T
Sikes, Elisabeth L
Hayward, Bruce William
Howard, William R
181-1125; COMPCORE; Composite Core; Joides Resolution; Leg181; Ocean Drilling Program; ODP; South Pacific Ocean
Planktonic foraminiferal census counts were converted to sea surface temperature (SST) estimates using the modern analogue technique (MAT) for the middle-late Pliocene (4.0-2.37 Ma) in ODP Site 1125, north side of Chatham Rise, SW Pacific Ocean. MAT SST(warm) records range between 8°C and 20.5°C, and MAT SST(cold) records parallel that pattern but with a temperature range of 5-15°C. The modern position of Site 1125 is just north of the Subtropical Front and has an annual temperature range of ~14-18°C. Pliocene warmest temperatures are 1-2° warmer than modern summers, whereas cold season SST records are up to 6-10°C cooler than modern winters. Overall average temperatures at the site are 2-3°C cooler than modern temperatures during a time of sustained global warmth. Three major cold excursions centred on 3.35, 3.0, and 2.8 Ma showed warm season temperatures over 5°C colder than the last glacial maximum, experiencing temperatures typical of modern subantarctic waters. Two minor cold excursions at 2.7 Ma and 2.4 Ma experienced temperatures cooler than modern winters but not as cold as last glacial conditions. Cold season SSTs show a shift to warmer climate upward through the study interval, whereas warm season estimates remain essentially unchanged. We interpret the strong regional cooling of subtropical Southwest Pacific water through the middle-late Pliocene as having been caused by increased upwelling. It is also possible that the subtropical frontal zone moved north over the site in the Pliocene, however, this is considered the least likely interpretation. Our record of cool conditions in the Southwest Pacific corroborate evidence of cooler than modern conditions in other regions of the western Pacific through the mid-Pliocene despite overall global warming.
title Pliocene foraminifera and SST changes in ODP Site 184-1125
topic 181-1125; COMPCORE; Composite Core; Joides Resolution; Leg181; Ocean Drilling Program; ODP; South Pacific Ocean
url https://doi.org/10.1594/PANGAEA.734790