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La deposición de carbonato, la estabilidad climática y las edades de hielo del Neoproterozoico
Andy J Ridgwell1, Martin J Kennedy, Ken Caldeira
1Department of Earth Sciences, University of California-Riverside, Riverside, CA 92521, USA. andyr@citrus.ucr.edu
Science (New York, N.Y.)
|November 1, 2003
Resumen
Los calcificadores plancticos evolucionaron durante el Fanerozoico, estabilizando el clima al amortiguar el carbonato oceánico. Esto preservó la química del océano, a diferencia del ciclo del carbono del Precámbrico.
Área de la Ciencia:
- La geoquímica es la geoquímica.
- Paleoclimatología Paleoclimatología
- Oceanografía La oceanografía es la oceanografía.
Sus antecedentes:
- El ciclo del carbono del Precámbrico fue sensible a los ambientes de aguas poco profundas y a las retroalimentaciones climáticas de CO2, lo que condujo a las edades de hielo del Neoproterozoico.
- El amortiguamiento del clima del Precámbrico dependía de la deposición de carbonato en aguas poco profundas que equilibraba las entradas de intemperie continental.
- La evolución de los calcificadores plancticos marcó un cambio significativo en la regulación del clima de la Tierra.
Objetivo del estudio:
- Para explicar la estabilización del sistema climático del Fanerozoico.
- Para dilucidar el papel de los calcificadores plancticos en el amortiguamiento de la concentración de iones de carbonato en el océano.
- Comprender las causas de las edades de hielo del Neoproterozoico y la formación de carbonatos en la capa.
Principales métodos:
- Análisis de la preservación de carbonatos en los sedimentos del fondo marino.
- Modelado de la dinámica de las concentraciones de iones de carbonato en el océano.
- Reconstrucción de los procesos del ciclo del carbono del Precámbrico y el Fanerozoico.
Principales resultados:
- Los calcificadores plancticos introdujeron la preservación dependiente de la saturación del carbonato, amortiguando la química del océano.
- Este nuevo mecanismo estabilizó el sistema climático durante el Fanerozoico.
- La inestabilidad climática del Precámbrico está relacionada con la ausencia de este mecanismo de amortiguación.
Conclusiones:
- La evolución de los calcificadores plancticos fue un evento crítico para la estabilización del clima.
- La preservación de carbonatos dependiente de la saturación es un regulador climático clave a largo plazo.
- La comprensión de la dinámica del ciclo del carbono pasado informa nuestro conocimiento de la sensibilidad del sistema terrestre.
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