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Measurement of Aerosols Optical Thickness of the Atmosphere using the GLOBE Handheld Sun Photometer
Published on: May 29, 2019
La visibilidad del cielo despejado ha disminuido sobre la tierra en todo el mundo desde 1973 hasta 2007
Kaicun Wang1, Robert E Dickinson, Shunlin Liang
1Department of Geography, University of Maryland, College Park, MD 20742, USA. kcwang@umd.edu
Science (New York, N.Y.)
|March 17, 2009
Resumen
El oscurecimiento global, causado por los aerosoles, ha aumentado desde mediados de la década de 1980, reduciendo la radiación solar. Mientras que Europa se está iluminando, otros continentes experimentan un empeoramiento de la visibilidad y un oscurecimiento.
Área de la Ciencia:
- Ciencias de la atmósfera Ciencias atmosféricas.
- Ciencias del clima Ciencias del clima Ciencias del clima
- Ciencias del medio ambiente Ciencias del medio ambiente.
Sus antecedentes:
- Los aerosoles tienen un impacto significativo en la radiación solar de la superficie de la Tierra al reducir la visibilidad.
- El oscurecimiento global, caracterizado por la disminución de la radiación solar, se observó hasta mediados de la década de 1980.
Objetivo del estudio:
- Para crear una climatología global de visibilidades inversas sobre la tierra desde 1973 hasta 2007.
- Para interpretar los cambios de visibilidad en términos de profundidad óptica del aerosol y los impactos de la radiación solar.
Principales métodos:
- Análisis de las visibilidades inversas sobre el terreno durante 35 años (1973-2007).
- Interpretación de las tendencias de visibilidad con respecto a la profundidad óptica del aerosol y la radiación solar incidente.
Principales resultados:
- La contribución de los aerosoles al oscurecimiento global ha aumentado monotónicamente a lo largo del período analizado.
- La visibilidad europea ha mejorado desde mediados de la década de 1980 (brillamiento europeo).
- La visibilidad ha disminuido en el sur y el este de Asia, América del Sur, Australia y África, lo que lleva a un oscurecimiento global neto sobre la tierra.
Conclusiones:
- El estudio establece una tendencia a largo plazo de aumento de oscurecimiento global sobre la tierra debido a los aerosoles.
- Las variaciones regionales en las tendencias de visibilidad son evidentes, con Europa iluminándose mientras que otros continentes se atenuan.
- Los cambios en la visibilidad impulsados por los aerosoles tienen implicaciones significativas para la radiación solar incidente a nivel mundial.
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