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Pequeña variabilidad interanual del hidroxilo atmosférico global
S A Montzka1, M Krol, E Dlugokencky
1NOAA Earth System Research Laboratory, Boulder, CO 80305, USA. stephen.a.montzka@noaa.gov
Science (New York, N.Y.)
|January 8, 2011
Resumen
La capacidad de oxidación atmosférica global, medida por los radicales hidroxilo (OH), muestra menos variabilidad interanual de lo que se pensaba anteriormente. Esto sugiere que la atmósfera es resistente a la contaminación y los cambios naturales, contrariamente a las interpretaciones anteriores de los datos de metilcloroformo (CH3CCl3).
Área de la Ciencia:
- Química de la atmósfera química de la atmósfera
- Ciencias del medio ambiente Ciencias del medio ambiente.
Sus antecedentes:
- La capacidad de oxidación atmosférica global está determinada principalmente por los radicales hidroxilo (OH).
- Las mediciones de metilcloroformo (CH3CCl3) se han utilizado para diagnosticar las concentraciones de OH e inferir la variabilidad interanual.
- Las interpretaciones anteriores sugirieron una sensibilidad significativa de la capacidad oxidante atmosférica a las perturbaciones.
Objetivo del estudio:
- Reevaluar la variabilidad interanual de las concentraciones globales medias de OH.
- Para evaluar la resiliencia de la capacidad oxidante atmosférica a las perturbaciones.
- Para refinar las estimaciones de la variabilidad de OH utilizando datos de CH3CCl3 posteriores a 1998.
Principales métodos:
- Análisis de las mediciones de metilcloroformo (CH3CCl3), especialmente después de 1998.
- Utilizando los gradientes atmosféricos disminuidos de CH3CCl3 debido al Protocolo de Montreal.
- Comparación con mediciones de metano y otros gases traza y modelos fotoquímicos globales.
Principales resultados:
- Se infería una variabilidad interanual significativamente menor en las concentraciones de OH.
- Las concentraciones globales de OH parecen estar bien amortiguadas contra las perturbaciones.
- La variabilidad refinada de OH es consistente con otras mediciones atmosféricas y cálculos de modelos.
Conclusiones:
- La atmósfera de la Tierra exhibe una mayor estabilidad en su capacidad de oxidación de lo que se estimaba anteriormente.
- El impacto del Protocolo de Montreal en las mediciones de CH3CCl3 mejoró las evaluaciones de la variabilidad de OH.
- Global OH es robusto y menos susceptible a las fluctuaciones ambientales a corto plazo.
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