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Concentraciones atmosféricas de aerosol de azufre y características del continente sudamericano
Science (New York, N.Y.)
|September 21, 1979
Resumen
Las muestras de aire de América del Sur revelan bajos niveles de azufre troposférico, lo que sugiere una concentración de fondo natural. Estos hallazgos pueden representar una línea de base para el azufre en aerosol en el modo de partículas finas.
Área de la Ciencia:
- Química de la atmósfera La química de la atmósfera
- Ciencias ambientales Ciencias ambientales.
- La geoquímica es la geoquímica.
Sus antecedentes:
- Las concentraciones de azufre en la troposfera son cruciales para comprender los procesos atmosféricos y la calidad del aire.
- Estudios anteriores sobre los niveles de azufre fuera de las ciudades, particularmente en el hemisferio norte, han arrojado valores más altos.
- El establecimiento de una línea de base para el azufre en aerosoles naturales es esencial para el monitoreo ambiental.
Objetivo del estudio:
- Para determinar la concentración de azufre de fondo troposférico en América del Sur.
- Para comparar los niveles de azufre de América del Sur con los reportados para el hemisferio norte.
- Para evaluar si las concentraciones medidas representan un nivel de fondo natural.
Principales métodos:
- Se recogieron muestras de aerosoles de ocho ubicaciones sudamericanas diferentes durante 1976-1977.
- Se utilizaron impactadores en cascada de seis etapas para analizar las concentraciones de azufre de partículas finas (aprox. 1 micrómetro de diámetro aerodinámico).
- Las muestras de filtro de secuencia temporal se analizaron para las concentraciones de azufre no relacionadas con la fumigación marina.
Principales resultados:
- La concentración de fondo de azufre troposférico en el modo de partículas finas fue de aproximadamente 50 nanogramos por metro cúbico de aire.
- Se encontró que la concentración promedio de azufre no relacionada con el rociado marino era de aproximadamente 85 nanogramos por metro cúbico.
- Estos valores sudamericanos son significativamente más bajos que los valores del hemisferio norte no urbano publicados anteriormente.
Conclusiones:
- Las concentraciones de azufre medidas en América del Sur pueden representar un nivel de fondo troposférico natural.
- Los hallazgos sugieren posibles diferencias regionales en la composición atmosférica de azufre.
- Se necesita más investigación para confirmar estos niveles de fondo natural y sus implicaciones.
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