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Los halógenos naturales de corta duración ejercen un efecto de enfriamiento indirecto sobre el clima

Alfonso Saiz-Lopez¹, Rafael P Fernandez^2,3, Qinyi Li^2,4

¹Department of Atmospheric Chemistry and Climate, Institute of Physical Chemistry Rocasolano, CSIC, Madrid, Spain. a.saiz@csic.es.

|June 28, 2023

Resumen

Los halógenos de corta duración emitidos por el océano causan un enfriamiento atmosférico significativo. Este efecto de enfriamiento, amplificado por las actividades humanas, ha aumentado desde los tiempos preindustriales e impacta el equilibrio radiativo de la Tierra.

Área de la Ciencia:

Química de la atmósfera
Ciencias del clima
Forzamiento radiativo

Sus antecedentes:

Los halógenos de corta duración emitidos por el océano están presentes globalmente en la atmósfera.
Las emisiones de halógenos naturales han sido amplificadas por las actividades antropogénicas desde la época preindustrial.
Los halocarburos de corta duración antropogénicos también se emiten a la atmósfera.

Objetivo del estudio:

Para cuantificar el impacto combinado de halógenos de corta duración en el equilibrio radiativo de la Tierra.
Evaluar los cambios históricos y las proyecciones futuras de este efecto radiativo.

Principales métodos:

Utilizó pruebas de observación y modelado atmosférico para determinar las perturbaciones radiativas.
Calculó el efecto radiativo indirecto de los halógenos, el ozono, el metano, los aerosoles y el vapor de agua estratosférico.

Principales resultados:

Los halógenos de corta duración ejercen un efecto de enfriamiento indirecto sustancial de -0,13 ± 0,03 vatios por metro cuadrado.
Este enfriamiento se compensa en parte por el calentamiento del metano, los aerosoles y el vapor de agua estratosférico.
El efecto de enfriamiento ha aumentado en un 61% desde 1750 debido a la amplificación antropogénica de las emisiones de halógenos naturales.

Conclusiones:

El efecto radiactivo indirecto de los halógenos de corta duración es significativo y ha aumentado históricamente.
Los cambios futuros en este efecto dependen de las proyecciones climáticas y del desarrollo socioeconómico.
Incorporar este efecto en los modelos climáticos es crucial para una línea de base realista del sistema climático de la Tierra.

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