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Cambios en la edad de las reservas superficiales de radiocarbono del mar Mediterráneo desde el último máximo glacial
1Laboratoire des Sciences du Climat et de l'Environnement (LSCE), Unité Mixte de Service, CNRS, Avenue de la Terrasse, F-91118 Gif-sur-Yvette, France.
Science (New York, N.Y.)
|December 1, 2001
Resumen
Las edades de los reservorios de la superficie del mar, cruciales para los estudios paleoclimáticos, se mantuvieron estables durante 18.000 años. Las edades se duplicaron durante la última deglaciación debido a los cambios en la circulación del Atlántico Norte.
Área de la Ciencia:
- La paleoceanografía es la paleoceanografía.
- Ciencias del clima Ciencias del clima Ciencias del clima
- La datación por radiocarbono fue
Sus antecedentes:
- Es esencial establecer un marco cronológico común para las paleoproxies marinas, continentales y criosféricas.
- La comprensión de las relaciones climáticas océano-continente y la paleoventilación oceánica se basa en edades exactas de las reservas de la superficie del mar.
Objetivo del estudio:
- Para determinar las edades de los reservorios de la superficie del mar en los últimos 18.000 años de carbono-14 en la región del Mediterráneo.
- Para investigar la influencia de los eventos climáticos pasados en las edades de las reservas oceánicas.
Principales métodos:
- La datación por radiocarbono de las foraminíferas planctónicas.
- Análisis de tefra depositada simultáneamente en registros marinos y terrestres.
Principales resultados:
- Las edades de los reservorios de la superficie del mar fueron consistentemente alrededor de 400 años durante la mayor parte de los últimos 18.000 años.
- Un aumento significativo (duplicación) en las edades de las reservas se produjo al inicio de la última deglaciación.
Conclusiones:
- Los cambios en la circulación termohalina del Atlántico Norte, vinculados al evento Heinrich 1, impactaron en las edades de los reservorios de la superficie del mar Mediterráneo.
- Estos hallazgos son críticos para refinar las reconstrucciones paleoclimáticas y comprender la dinámica oceánica.
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