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Magnitud y momento del cambio de temperatura en la piscina cálida del Indo-Pacífico durante la deglaciación
Katherine Visser1, Robert Thunell, Lowell Stott
1Department of Geological Sciences, University of South Carolina, Columbia, South Carolina 29205, USA.
Nature
|January 10, 2003
Resumen
Las temperaturas de la superficie del mar del Pacífico tropical aumentaron significativamente durante los ciclos glacial-interglacial, que precedieron al derretimiento de la capa de hielo del hemisferio norte. Esto sugiere que el Pacífico tropical es un motor clave de la Tierra.
Área de la Ciencia:
- Paleoclimatología Paleoclimatología
- Interacciones entre el océano y la atmósfera.
- Dinámica del sistema climático Dinámica del sistema climático
Sus antecedentes:
- Las interacciones entre el océano tropical del Pacífico y la atmósfera influyen significativamente en el calor global y el transporte de vapor de agua, lo que afecta al sistema climático.
- Si bien los cambios tropicales del Indo-Pacífico explican la variabilidad climática interanual a decadal, su papel en los cambios climáticos milenarios y orbitales sigue sin estar claro.
Objetivo del estudio:
- Investigar el papel de la región tropical del Indo-Pacífico en los cambios climáticos glaciales e interglaciales en escalas de tiempo milenarias y orbitales.
- Para obtener estimaciones sincrónicas de las temperaturas de la superficie del mar y los cambios en el volumen de hielo durante las transiciones climáticas pasadas.
Principales métodos:
- Análisis de los isótopos de oxígeno y las relaciones Mg/Ca en conchas foraminiferales del estrecho de Makassar.
- Reconstrucción de las temperaturas de la superficie del mar y el volumen de hielo utilizando proxies geoquímicos.
Principales resultados:
- Las temperaturas de la superficie del mar en el Pacífico tropical aumentaron en 3.5-4.0°C durante las dos últimas transiciones glacial-interglacial.
- Este calentamiento fue sincrónico con el aumento del CO2 atmosférico y el calentamiento de la Antártida.
- El calentamiento del Pacífico tropical precedió al derretimiento de la capa de hielo del hemisferio norte en 2.000-3.000 años.
Conclusiones:
- La región tropical del Pacífico juega un papel crucial en la conducción de los ciclos glaciales-interglaciales.
- Esta influencia puede operar a través de mecanismos similares a la regulación de El Niño / Oscilación del Sur del calor hacia los polos y el flujo de vapor de agua.
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