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Redistribución glacial al Holoceno del ion carbonato en las profundidades marinas
1Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY 10964, USA. broecker@ldeo.columbia.edu
Science (New York, N.Y.)
|December 12, 2001
Resumen
Los océanos glaciales presentaban distintos gradientes de concentración de iones de carbonato. A diferencia de hoy, las aguas profundas del Pacífico vieron aumentar las concentraciones con la profundidad, mientras que las aguas atlánticas las vieron disminuir, lo que indica un mayor contraste oceanográfico.
Área de la Ciencia:
- La paleoceanografía es la paleoceanografía.
- La geoquímica marina es la geoquímica marina.
- Oceanografía La oceanografía es la oceanografía.
Sus antecedentes:
- Comprender las condiciones oceánicas pasadas es crucial para predecir el cambio climático futuro.
- La concentración de iones de carbonato es un factor clave que influye en la química del océano y la vida marina.
Objetivo del estudio:
- Para reconstruir la distribución de la concentración de iones carbonato en el océano ecuatorial profundo durante el último período glacial.
- Para comparar la química de carbonato de los océanos profundos de la era glacial con las condiciones modernas.
Principales métodos:
- Análisis de las diferencias de peso de la concha de foraminifera entre los especímenes glaciales y del Holoceno.
- Muestreo de núcleos de sedimentos de la elevación de Ceara (oeste del Atlántico) y la meseta de Java Ontong (oeste del Pacífico).
- Reconstrucción de gradientes verticales de profundidad del agua en la concentración de iones de carbonato.
Principales resultados:
- Gradientes verticales significativos en la concentración de iones de carbonato estaban presentes en el océano profundo de la era glacial.
- En el Pacífico ecuatorial, la concentración de iones carbonato aumentó con la profundidad durante los períodos glaciales.
- En el Atlántico, la concentración de iones carbonato disminuyó con la profundidad durante los períodos glaciales.
Conclusiones:
- La química de los carbonatos de los océanos profundos de la era glacial difería sustancialmente de la del océano actual.
- Un mayor contraste en la concentración de iones de carbonato existía entre las aguas profundas del Atlántico Norte y el Pacífico durante las épocas glaciales.
- Estos hallazgos resaltan cambios significativos en la circulación oceánica y el ciclo del carbono durante las edades de hielo pasadas.
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