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Concentración de aerosoles en la capa límite amazónica sostenida por el transporte vertical durante las lluvias
Jian Wang1, Radovan Krejci2, Scott Giangrande1
1Environmental and Climate Sciences Department, Brookhaven National Laboratory, Upton, New York 11973, USA.
Nature
|November 4, 2016
Resumen
Los vapores atmosféricos nuclean nuevas partículas de aerosoles. En el Amazonas, la precipitación transporta estas partículas de la troposfera libre a la capa límite, lo que influye en las propiedades de las nubes.
Área de la Ciencia:
- Ciencias atmosféricas
- Ciencia de los aerosoles
- Física de las nubes
Sus antecedentes:
- La nucleación de vapor atmosférico forma nuevas partículas de aerosol, cruciales para los núcleos de condensación de nubes (CCN).
- Los estudios de aerosoles continentales a menudo están influenciados por fuentes antropogénicas, dejando ambientes prístinos poco estudiados.
- La selva amazónica ofrece un entorno único para estudiar los procesos de aerosoles casi naturales.
Objetivo del estudio:
- Investigar el origen de pequeñas partículas de aerosol en la capa límite del Amazonas.
- Para entender los procesos que mantienen las poblaciones de partículas que influyen en la formación de nubes en un entorno prístino.
Principales métodos:
- Mediciones aéreas y terrestres realizadas en la cuenca central del Amazonas durante la temporada de lluvias.
- Centrarse en las concentraciones de partículas de aerosoles y los mecanismos de transporte vertical en condiciones atmosféricas limpias.
Principales resultados:
- Se observaron altas concentraciones de pequeñas partículas de aerosol (diámetro < 50 nm) en la troposfera libre inferior.
- Los eventos de precipitación, incluidos los flujos descendentes convectivos y los flujos descendentes de regiones estratiformes, se identificaron como mecanismos de transporte clave.
- Estos procesos mueven partículas de la troposfera libre hacia la capa límite del Amazonas.
Conclusiones:
- El rápido transporte vertical de partículas de aerosol durante los eventos de precipitación mantiene las poblaciones de partículas en la capa límite del Amazonas.
- Este mecanismo es vital para comprender las interacciones entre aerosoles y nubes y la regulación del clima en entornos terrestres naturales.
- Los hallazgos resaltan la importancia de los entornos prístinos para el estudio de los procesos atmosféricos fundamentales.
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