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Transporte atmosférico de largo alcance de polvo del suelo de Asia al Pacífico norte tropical: variabilidad temporal
Science (New York, N.Y.)
|September 26, 1980
Resumen
Las concentraciones de polvo en el suelo en el Atolón Enewetak disminuyeron significativamente durante cinco meses en 1979. Este polvo, probablemente de China, puede contribuir sustancialmente a los sedimentos de aguas profundas del Pacífico Norte.
Área de la Ciencia:
- Ciencias de la atmósfera Ciencias atmosféricas.
- Oceanografía La oceanografía es la oceanografía.
- La geoquímica es la geoquímica.
Sus antecedentes:
- El atolón Enewetak es una ubicación remota en el Océano Pacífico, lo que lo convierte en un sitio adecuado para monitorear el transporte atmosférico de largo alcance.
- Comprender las fuentes y las tasas de deposición de polvo en el aire es crucial para interpretar la composición de los sedimentos marinos y los registros paleoclimáticos.
Objetivo del estudio:
- Para cuantificar la concentración y las tendencias temporales del polvo del suelo en el aire en el atolón Enewetak.
- Investigar el posible origen y la importancia deposicional de los eventos de polvo observados.
Principales métodos:
- Se recogieron partículas en suspensión en el aire y se analizaron las concentraciones de polvo en el suelo.
- Las tendencias temporales en la concentración de polvo se analizaron durante un período de cinco meses.
Principales resultados:
- La concentración de polvo del suelo en el aire en el atolón Enewetak se midió en 2,3 μg/m3 en abril de 1979.
- Las concentraciones disminuyeron constantemente a 0,02 μg/m3 en septiembre de 1979.
- La tasa de deposición se estimó en aproximadamente 0.3 mm por 1000 años.
Conclusiones:
- El evento de polvo de primavera observado en el atolón Enewetak probablemente se originó en fuentes del este de Asia, como China.
- La tasa de deposición calculada sugiere que este polvo es un contribuyente potencial significativo a los sedimentos de aguas profundas del Pacífico Norte.
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