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Un sumidero neto para el CH3Br atmosférico en el Océano Pacífico Este
Science (New York, N.Y.)
|February 17, 1995
Resumen
Las aguas superficiales en el Océano Pacífico oriental están en su mayoría insaturadas en bromuro de metilo (CH3Br), excepto cerca de las costas. Este sumidero oceánico influye en la distribución atmosférica de CH3Br y su diferencia interhemisférica.
Área de la Ciencia:
- Química marina La química marina es la química de las aguas marinas.
- Química de la atmósfera química de la atmósfera
- Interacciones entre el océano y la atmósfera.
Sus antecedentes:
- El bromuro de metilo (CH3Br) es una sustancia que agota la capa de ozono de manera significativa.
- Comprender las fuentes y sumideros oceánicos de CH3Br es crucial para el modelado atmosférico.
Objetivo del estudio:
- Para evaluar la saturación de bromuro de metilo en las aguas superficiales del Pacífico oriental.
- Para cuantificar la tasa de degradación oceánica del CH3Br.Br atmosférico.
- Para investigar el papel de la distribución oceánica de CH3Br en las diferencias interhemisféricas.
Principales métodos:
- Realizando un estudio de la pista de cruceros en el Océano Pacífico Este.
- Medición de las concentraciones de CH3Br en aguas superficiales.
- Cálculo de anomalías de saturación y vidas parciales.
Principales resultados:
- Las aguas superficiales estaban en gran medida insaturadas en CH3Br, con anomalías de +100% (costales) a -50% (océano abierto).
- Se calculó que el tiempo medio de vida parcial de degradación oceánica del CH3Br atmosférico es de 3,0 años.
- Las fuentes y sumideros oceánicos contribuyeron aproximadamente un 8% a la diferencia interhemisférica de CH3Br observada.
Conclusiones:
- El Océano Pacífico Este actúa como un sumidero neto para el bromuro de metilo atmosférico.
- La desigual distribución oceánica del CH3Br tiene un impacto significativo en sus concentraciones atmosféricas globales.
- Los procesos oceánicos son factores clave en la regulación de los niveles atmosféricos de CH3Br.
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