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El tamaño importa más que la química para la capacidad de núcleo de nubes de las partículas de aerosol
U Dusek1, G P Frank, L Hildebrandt
1Department of Biogeochemistry, Max Planck Institute for Chemistry, Mainz 55128, Germany.
Science (New York, N.Y.)
|June 3, 2006
Resumen
Las concentraciones de núcleos de condensación de nubes (CCN) están impulsadas principalmente por la distribución del tamaño del aerosol, no por la composición química. Este hallazgo simplifica el modelado de los impactos de los aerosoles en la física de las nubes en modelos climáticos globales y regionales.
Área de la Ciencia:
- Ciencias de la atmósfera Ciencias atmosféricas.
- Física de las nubes Física de las nubes.
- Ciencia de los aerosoles Ciencia de los aerosoles.
Sus antecedentes:
- Los núcleos de condensación de nubes (CCN) son esenciales para la formación de nubes.
- Las propiedades de los aerosoles, incluyendo el tamaño y la composición química, influyen en la activación de la CCN.
- La representación precisa de CCN es crucial para el modelado climático.
Objetivo del estudio:
- Para investigar los principales impulsores de las concentraciones de CCN.
- Para determinar la importancia relativa del tamaño del aerosol frente a la composición química en la activación de la CCN.
- Para mejorar la parametrización de las interacciones aerosol-nube en los modelos climáticos.
Principales métodos:
- Las mediciones con resolución de tamaño de los espectros de CCN se llevaron a cabo en un sitio no urbano alemán.
- El análisis de los datos se centró en la correlación de las concentraciones de CCN con la distribución numérica del tamaño del aerosol y la composición química.
- Se utilizaron métodos estadísticos para cuantificar la contribución del tamaño y la composición a la variación de la CCN.
Principales resultados:
- Las concentraciones de CCN se determinaron predominantemente por la distribución numérica del tamaño del aerosol.
- Si bien la composición química mostró distintas variaciones en la activación de la CCN, su papel fue secundario.
- La distribución del tamaño del aerosol por sí sola explicó del 84% al 96% de la variación en las concentraciones de CCN cuando se ignoraron los efectos químicos temporales.
Conclusiones:
- El tamaño del aerosol es el factor dominante que controla la activación de la CCN.
- El tratamiento simplificado de los efectos de los aerosoles en la física de las nubes es factible al priorizar la distribución de tamaño en los modelos.
- Esta investigación facilita un modelado climático más preciso de las interacciones aerosol-nube.
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