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Measuring Carbon-based Contaminant Mineralization Using Combined CO2 Flux and Radiocarbon Analyses
Published on: October 21, 2016
Sincrónico radiocarbono y cambios climáticos durante la última deglaciación
K A Hughen1, J R Southon, S J Lehman
1Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA. khughen@whoi.edu
Science (New York, N.Y.)
|January 11, 2000
Resumen
La datación por radiocarbono revela importantes fluctuaciones atmosféricas de carbono-14 durante la desglaciación, coincidiendo con el evento de enfriamiento del Dryas más joven. Estos cambios probablemente fueron el resultado de cambios abruptos en la ventilación de las profundidades oceánicas.
Área de la Ciencia:
- Paleoclimatología Paleoclimatología
- Las citas radiométricas.
- Oceanografía La oceanografía es la oceanografía.
Sus antecedentes:
- La escala de tiempo del carbono-14 (14C) requiere calibración, especialmente durante eventos climáticos pasados.
- Las reconstrucciones anteriores de los cambios atmosféricos del 14C carecían de alta resolución durante el período de deglaciación.
Objetivo del estudio:
- Para calibrar la escala de tiempo del 14C utilizando datos de alta resolución de la cuenca del Cariaco.
- Investigar la relación entre las variaciones atmosféricas de 14C y los cambios climáticos abruptos durante la deglaciación.
Principales métodos:
- Análisis de datos de radiocarbono de núcleos de sedimentos de la cuenca de Cariaco.
- Comparación de datos de 14C con datos de berilio-10 (10Be) y registros de paleoclima.
Principales resultados:
- Calibración 14C de alta resolución del período de deglaciación (hace 15.000-10.000 años).
- Los cambios de 14C atmosféricos reconstruidos fueron mayores de lo estimado previamente.
- La excursión más significativa de 14C ocurrió simultáneamente con el evento de enfriamiento de Younger Dryas.
Conclusiones:
- Se proponen cambios abruptos en la ventilación de los océanos profundos como el principal impulsor de los cambios climáticos y 14C concurrentes.
- Los hallazgos vinculan los procesos oceánicos directamente con la composición atmosférica y los cambios climáticos durante un período crítico de la historia de la Tierra.
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