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Tendencias atmosféricas en metilcloroformo y el promedio global para el radical hidroxilo

R Prinn, D Cunnold, R Rasmussen

Science (New York, N.Y.)

|November 13, 1987

Resumen

Los niveles atmosféricos de metilcloroformo están aumentando a nivel mundial. Los científicos determinaron su vida atmosférica y la concentración de radicales hidroxilo, cruciales para comprender la química atmosférica.

Área de la Ciencia:

Química de la atmósfera química de la atmósfera
Ciencias del medio ambiente Ciencias del medio ambiente.

Sus antecedentes:

El metilcloroformo es un compuesto antropogénico con una significativa presencia atmosférica global.
Su principal mecanismo de eliminación es la reacción con los radicales hidroxilo (OH).

Objetivo del estudio:

Para determinar el tiempo de vida atmosférico global del metilcloroformo.
Para estimar la concentración promedio global de radicales hidroxilo troposféricos.
Para refinar la comprensión de los ciclos químicos atmosféricos.

Principales métodos:

Análisis de las frecuentes mediciones atmosféricas de metilcloroformo de 1978 a 1985.
Utilizando un esquema de inversión de estimación óptima que combina mediciones y datos de emisiones industriales.
Realiza aproximadamente 60.000 análisis cromatográficos de aire calibrados por gas.

Principales resultados:

Las tendencias anuales medias observadas para el metilcloroformo oscilan entre el 4,8% y el 6,9% en varios sitios globales.
Dedujo una vida atmosférica promedio global de metilcloroformo de 6,3 años (con incertidumbre).
Se estima una concentración promedio global de radicales hidroxilo troposféricos de 7.7 x 10^5 radicales/cm3 (con incertidumbre).

Conclusiones:

El estudio proporciona las estimaciones más precisas hasta la fecha para las tendencias y la vida útil del metilcloroformo.
La concentración exacta de radicales hidroxilo es vital para comprender los ciclos químicos atmosféricos.
Esta investigación es crucial para comprender las tendencias en los gases traza como el metano.

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