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Eliminación del hierro meteórico en las nubes mesosféricas polares
John M C Plane1, Benjamin J Murray, Xinzhao Chu
1School of Environmental Sciences, University of East Anglia, Norwich NR4 7TJ, UK. j.plane@uea.ac.uk
Science (New York, N.Y.)
|April 17, 2004
Resumen
Las nubes mesosféricas polares eliminan eficientemente los átomos de hierro de la atmósfera. Esta interacción, observada a través de lidar en el Polo Sur, es impulsada por la absorción de hierro en las partículas de hielo de la nube.
Área de la Ciencia:
- Ciencias de la atmósfera Ciencias atmosféricas.
- La aeronomía es la aeronomía.
- Física de las nubes Física de las nubes.
Sus antecedentes:
- Las nubes mesosféricas polares (PMC) son capas de partículas de hielo en la mesosfera superior.
- Estas nubes se forman cerca de la altitud de las capas atmosféricas de hierro (Fe).
- La ablación de meteoritos es la principal fuente de hierro atmosférico.
Objetivo del estudio:
- Para investigar la interacción entre las nubes mesosféricas polares y los átomos de hierro atmosféricos.
- Para determinar el mecanismo responsable de la eliminación de Fe en presencia de PMCs.
Principales métodos:
- Observaciones simultáneas con lidar de PMC y capas de Fe en el Polo Sur.
- Experimentos de laboratorio que simulan las interacciones de las partículas de hielo Fe.
- Modelado atmosférico para interpretar datos observacionales y experimentales.
Principales resultados:
- Los datos de Lidar revelaron una eliminación casi completa de los átomos de Fe dentro de las altitudes del PMC.
- Los estudios de laboratorio confirmaron la absorción eficiente de Fe en las superficies de las partículas de hielo.
- El modelado apoyó la hipótesis de la deposición superficial como el mecanismo de eliminación.
Conclusiones:
- Las nubes mesosféricas polares juegan un papel importante en la eliminación del hierro atmosférico.
- La interacción se rige por la química física de la adsorción de Fe en las partículas de hielo.
- Este proceso afecta el presupuesto y la distribución de los metales en la atmósfera superior.
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