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La pérdida de ozono en el Ártico debido a la desnitrificación
1Max-Planck-Institut fur Chemie, Post Office Box 3060, 55020 Mainz, Germany. Forschungszentrum Karlsruhe, Institut fur Meteorologie und Klimaforschung, Post Office Box 3640, D-76021 Karlsruhe, Germany. FU Berlin, Institut fur Meteorologie, Carl-Heinr.
Science (New York, N.Y.)
|March 26, 1999
Resumen
La desnitrificación del Ártico, impulsada por partículas de trihidrato de ácido nítrico, aumenta significativamente el agotamiento del ozono. El futuro enfriamiento estratosférico puede retrasar la recuperación del ozono hasta finales del siglo XXI.
Área de la Ciencia:
- Química de la atmósfera La química de la atmósfera
- Ciencia de la estratosfera Ciencia de la estratosfera.
- Modelado del clima Modelado del clima
Sus antecedentes:
- El agotamiento de la capa de ozono en el Ártico es una preocupación ambiental significativa.
- El nitrógeno reactivo estratosférico juega un papel crucial en la química del ozono.
- La sedimentación de partículas es un proceso conocido en la estratosfera.
Objetivo del estudio:
- Para investigar el papel de la sedimentación de partículas en la desnitrificación del Ártico.
- Cuantificar el impacto de la desnitrificación en la pérdida de ozono en el Ártico.
- Evaluar la trayectoria futura de la recuperación del ozono en el Ártico.
Principales métodos:
- Restringir un modelo microfísico con datos de observación de 1994-95.
- Simulación de procesos de desnitrificación y su impacto en el ozono.
- Realización de estudios de sensibilidad sobre las condiciones estratosféricas.
Principales resultados:
- La desnitrificación es causada principalmente por partículas de trihidrato de ácido nítrico en bajas densidades.
- La desnitrificación aumenta sustancialmente la pérdida de ozono en el Ártico.
- La estratosfera ártica está cerca de un umbral de desnitrificación.
Conclusiones:
- El aumento del dióxido de carbono antropogénico puede conducir a un enfriamiento estratosférico.
- Es probable que el enfriamiento futuro aumente la desnitrificación.
- Se proyecta que la recuperación del ozono ártico se retrasará hasta finales del siglo XXI.
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