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Ceniza volcánica sobre Arizona en la primavera de 1982: Observaciones astronómicas
Science (New York, N.Y.)
|April 15, 1983
Resumen
Las nubes de polvo volcánico impactaron significativamente en Arizona.
Área de la Ciencia:
- Ciencias de la atmósfera ciencia atmosférica.
- Volcanología Volcanología.
- La astronomía es la astronomía.
Sus antecedentes:
- Las erupciones volcánicas pueden inyectar polvo y aerosoles en la atmósfera.
- Los aerosoles atmosféricos pueden afectar las observaciones astronómicas al aumentar la extinción.
- La erupción de El Chichón en 1982 proporcionó una fuente potencial de nubes de polvo volcánico en el hemisferio norte.
Objetivo del estudio:
- Para documentar y analizar el paso de nubes de polvo volcánico sobre Arizona en 1982.
- Para cuantificar el impacto del polvo volcánico en la extinción atmosférica.
- Para investigar las propiedades de absorción de la nube de polvo volcánico.
Principales métodos:
- Observaciones astronómicas de la extinción atmosférica en longitudes de onda visibles.
- Análisis de mediciones ópticas de profundidad.
- Comparación de datos de extinción de múltiples ubicaciones (Tucson y Flagstaff).
Principales resultados:
- Las observaciones astronómicas revelaron la presencia de una, posiblemente más, nubes de polvo volcánico entre enero y junio de 1982.
- El 15 de mayo, la extinción atmosférica aumentó en más de un 40% (0,4 profundidad óptica) en Tucson y un 25% en Flagstaff.
- Se encontraron evidencias de la absorción no gris por la nube de polvo volcánico.
Conclusiones:
- Las nubes de polvo volcánico afectaron significativamente la transparencia atmosférica en Arizona a principios de 1982.
- Los niveles de extinción observados tuvieron un impacto notable en las observaciones astronómicas.
- El estudio proporciona un registro detallado de la extinción atmosférica y las propiedades de la nube de polvo.
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