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Evolution of Staircase Structures in Diffusive Convection
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La evolución deglacial de la convección profunda del Atlántico Norte
David J R Thornalley1, Stephen Barker, Wallace S Broecker
1School of Earth and Ocean Sciences, Cardiff University, Cardiff, CF10 3YE, UK. d.thornalley@cantab.net
Science (New York, N.Y.)
|January 15, 2011
Resumen
La formación de aguas profundas en el Atlántico Norte, crucial para la circulación oceánica y la regulación del clima, disminuyó durante los períodos fríos. Esto permitió que el Agua Intermedia Antártica entrara, impactando la circulación atmosférica.
Área de la Ciencia:
- Oceanografía La oceanografía es la oceanografía.
- Paleoclimatología Paleoclimatología
- Ciencias del clima Ciencias del clima Ciencias del clima
Sus antecedentes:
- La formación de aguas profundas en el Atlántico Norte es clave para la circulación volcada del Océano Atlántico y la regulación climática global.
- La convección del océano abierto impulsa este proceso de formación de aguas profundas.
Objetivo del estudio:
- Para investigar los cambios en la formación y convección de aguas profundas del Atlántico Norte desde el Último Máximo Glacial.
- Comprender la relación entre la convección del Atlántico Norte y la regulación climática global.
Principales métodos:
- Utilizó reconstrucciones de radiocarbono de la columna de agua para analizar patrones de convección pasados.
- Comparación de cambios temporales en la convección profunda entre el noreste y el noroeste del Atlántico.
Principales resultados:
- Inferida reducción de la convección en el océano abierto en el Atlántico nororiental durante intervalos fríos.
- Identificó una incursión de agua intermedia antártica extremadamente empobrecida de radiocarbono durante estos períodos fríos.
- Se observó que la convección reducida tanto en el noreste como en el noroeste del Atlántico es necesaria para explicar los cambios en la circulación atmosférica.
Conclusiones:
- La convección del Atlántico nororiental influye significativamente en las temperaturas de Groenlandia.
- Las reducciones sincronizadas en la convección del océano abierto del Atlántico Norte están vinculadas a perturbaciones en la circulación atmosférica.
- Las incursiones de agua intermedia en la Antártida se correlacionan con la reducción de la formación de aguas profundas durante las etapas frías glaciales.
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