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El enfriamiento del Pacífico oriental y la circulación de volteo del Atlántico durante la última deglaciación
Markus Kienast1, Stephanie S Kienast, Stephen E Calvert
1Department of Oceanography, Dalhousie University, Halifax, Nova Scotia, B3H 4J1 Canada. markus.kienast@dal.ca
Nature
|October 20, 2006
Resumen
Los cambios climáticos globales durante las edades de hielo pueden deberse a cambios en la circulación oceánica. El enfriamiento del Océano Pacífico durante los períodos fríos del Atlántico Norte sugiere un vínculo global, no solo efectos regionales.
Área de la Ciencia:
- La paleoceanografía es la paleoceanografía.
- Ciencias del clima Ciencias del clima Ciencias del clima Ciencias del clima
- Oceanografía La oceanografía es la oceanografía.
Sus antecedentes:
- Se debaten los cambios climáticos a escala milenaria durante los períodos glaciales.
- El papel de las temperaturas superficiales del mar del Pacífico tropical en estos cambios no está claro.
- Estudios anteriores vincularon los períodos fríos del Atlántico Norte con el clima global, pero no con el Pacífico.
Objetivo del estudio:
- Para investigar el vínculo entre los períodos fríos del Atlántico Norte y las temperaturas de la superficie del mar en el Pacífico tropical.
- Para determinar si los cambios en la circulación oceánica impulsaron cambios climáticos globales.
Principales métodos:
- Reconstrucción de alta resolución de la temperatura de la superficie del mar utilizando insaturación de alquenonas.
- Análisis de los flujos de enterramiento de carbono para inferir la productividad del océano y el surgimiento.
- Datación de los registros paleoceanográficos para establecer la sincronicidad temporal.
Principales resultados:
- Una caída de la temperatura de la superficie del mar de ~ 1 ° C en el Pacífico tropical oriental durante el evento Heinrich 1.
- Una caída de la temperatura de la superficie del mar de ~ 0.5 ° C durante el evento Younger Dryas.
- Aumentos coincidentes en la productividad de la superficie oceánica, lo que indica un aumento de la subida de aguas durante ambos períodos fríos.
Conclusiones:
- El enfriamiento del Pacífico ecuatorial ocurrió sincrónicamente con los períodos fríos del Atlántico Norte.
- Estos hallazgos sugieren que los cambios climáticos a escala milenaria fueron impulsados por la reorganización de la circulación termohalina oceánica.
- Las interacciones entre el océano tropical y la atmósfera pueden haber amplificado estos cambios climáticos.
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