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Impacto del CO2 antropogénico en el sistema CaCO3 en los océanos
Richard A Feely1, Christopher L Sabine, Kitack Lee
1Pacific Marine Environmental Laboratory, National Oceanic and Atmospheric Administration, Seattle, WA 98115-6349, USA. richard.a.feely@noaa.gov
Science (New York, N.Y.)
|July 17, 2004
Resumen
La acidificación de los océanos por el aumento del dióxido de carbono (CO2) aumenta la disolución del carbonato de calcio (CaCO3). Las tasas de disolución de CaCO3 en el océano global se estiman en 0,5 petagramos de CaCO3-C por año, lo que afecta a las especies formadoras de conchas.
Área de la Ciencia:
- Oceanografía La oceanografía es la oceanografía.
- Química marina La química marina es la química de las aguas.
- Ciencias del clima Ciencias del clima Ciencias del clima Ciencias del clima
Sus antecedentes:
- El aumento de las concentraciones de dióxido de carbono atmosférico (CO2) durante dos siglos ha aumentado la absorción de CO2 oceánico.
- Este proceso ha llevado a la acidificación de los océanos, alterando el estado de saturación de las partículas de carbonato de calcio (CaCO3).
Objetivo del estudio:
- Para estimar in situ las tasas de disolución de CaCO3 en los océanos globales.
- Para discutir los impactos futuros del CO2 antropogénico en las especies formadoras de conchas de CaCO3.
Principales métodos:
- Se utilizaron datos de alcalinidad total y clorofluorocarburos (CFC) para estimar las tasas de disolución de CaCO3.
- Los datos analizados para determinar las tasas de disolución en micromoles por kilogramo por año.
Principales resultados:
- Se observaron tasas de disolución de CaCO3 que oscilaban entre 0,003 y 1,2 micromoles por kilogramo por año.
- La disolución comienza cerca del horizonte de saturación de la aragonita.
- La tasa de disolución de CaCO3 en el océano global se estima en aproximadamente 0,5 +/- 0,2 petagramos de CaCO3-C por año.
Conclusiones:
- La tasa de disolución global estimada de CaCO3 representa entre el 45 y el 65% de la producción total de exportación de CaCO3.
- La acidificación de los océanos representa una amenaza significativa para los ecosistemas marinos, en particular los organismos formadores de conchas.
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