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Nuevas restricciones observacionales para el hidroxilo atmosférico en escalas globales y hemisféricas
1National Oceanic and Atmospheric Administration, Climate Monitoring and Diagnostics Laboratory, 325 Broadway, Boulder, CO 80303, USA. Department of Earth and Planetary Sciences and Division of Engineering and Applied Sciences, Harvard Univ.
Science (New York, N.Y.)
|April 25, 2000
Resumen
Las reducciones en las emisiones de metilcloroformo (1,1,1-tricloroetano) revelan el poder oxidante atmosférico. Las concentraciones de radicales hidroxilo son más altas en el hemisferio sur, lo que afecta la química atmosférica.
Área de la Ciencia:
- Química de la atmósfera química de la atmósfera
- Ciencias del medio ambiente Ciencias del medio ambiente.
- Investigación del Cambio Climático Investigación del Cambio Climático
Sus antecedentes:
- El Protocolo de Montreal redujo significativamente las emisiones de metilcloroformo (1,1,1-tricloroetano).
- El metilcloroformo es un trazador clave para comprender los procesos de oxidación atmosférica.
Objetivo del estudio:
- Evaluar el impacto de las emisiones reducidas de metilcloroformo en la capacidad de oxidación atmosférica.
- Para determinar la carga global y la distribución del radical hidroxilo (OH).
Principales métodos:
- Utilizó observaciones atmosféricas de metilcloroformo de finales de la década de 1990.
- Se analizaron los datos para establecer los límites superiores de la vida útil del metilcloroformo.
- Concentraciones cuantificadas de radicales hidroxilo en diferentes latitudes.
Principales resultados:
- Se determinó una vida útil global para el metilcloroformo de 5,2 años y una vida útil en el hemisferio sur de 4,9 años.
- Confirmó el dominio del radical hidroxilo en los trópicos.
- Se encontraron concentraciones de OH un 15% más altas al sur de la zona de convergencia intertropical en comparación con el norte.
Conclusiones:
- La reducción de las emisiones de metilcloroformo ofrece información sobre la distribución atmosférica de los radicales hidroxilo.
- Se confirma la distribución asimétrica de radicales hidroxilo entre los hemisferios.
- El estudio proporciona datos cruciales para los modelos atmosféricos y las evaluaciones del cambio climático.
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