Climate hypersensitivity to solar forcing?

We compare the equilibrium climate responses of a quasi-dynamical energy balance model to radiative forcing by equivalent changes in CO2, solar total irradiance (Stot) and solar UV (SUV). The response is largest in the SUV case, in which the imposed UV radiative forcing is preferentially absorbed in...

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Main Authors: Soon, W., Posmentier, E., Baliunas, S.
Format: Article
Language:English
Published: European Geosciences Union 2000
Online Access:http://psasir.upm.edu.my/id/eprint/115698/
http://psasir.upm.edu.my/id/eprint/115698/1/115698.pdf
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author Soon, W.
Posmentier, E.
Baliunas, S.
author_facet Soon, W.
Posmentier, E.
Baliunas, S.
author_sort Soon, W.
building UPM Institutional Repository
collection Online Access
description We compare the equilibrium climate responses of a quasi-dynamical energy balance model to radiative forcing by equivalent changes in CO2, solar total irradiance (Stot) and solar UV (SUV). The response is largest in the SUV case, in which the imposed UV radiative forcing is preferentially absorbed in the layer above 250 mb, in contrast to the weak response from global-columnar radiative loading by increases in CO2 or Stot. The hypersensitive response of the climate system to solar UV forcing is caused by strongly coupled feedback involving vertical static stability, tropical thick cirrus ice clouds and stratospheric ozone. This mechanism offers a plausible explanation of the apparent hypersensitivity of climate to solar forcing, as suggested by analyses of recent climatic records. The model hypersensitivity strongly depends on climate parameters, especially cloud radiative properties, but is effective for arguably realistic values of these parameters. The proposed solar forcing mechanism should be further confirmed using other models (e.g., general circulation models) that may better capture radiative and dynamical couplings of the troposphere and stratosphere.
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spelling upm-1156982025-03-10T07:43:21Z http://psasir.upm.edu.my/id/eprint/115698/ Climate hypersensitivity to solar forcing? Soon, W. Posmentier, E. Baliunas, S. We compare the equilibrium climate responses of a quasi-dynamical energy balance model to radiative forcing by equivalent changes in CO2, solar total irradiance (Stot) and solar UV (SUV). The response is largest in the SUV case, in which the imposed UV radiative forcing is preferentially absorbed in the layer above 250 mb, in contrast to the weak response from global-columnar radiative loading by increases in CO2 or Stot. The hypersensitive response of the climate system to solar UV forcing is caused by strongly coupled feedback involving vertical static stability, tropical thick cirrus ice clouds and stratospheric ozone. This mechanism offers a plausible explanation of the apparent hypersensitivity of climate to solar forcing, as suggested by analyses of recent climatic records. The model hypersensitivity strongly depends on climate parameters, especially cloud radiative properties, but is effective for arguably realistic values of these parameters. The proposed solar forcing mechanism should be further confirmed using other models (e.g., general circulation models) that may better capture radiative and dynamical couplings of the troposphere and stratosphere. European Geosciences Union 2000 Article PeerReviewed text en http://psasir.upm.edu.my/id/eprint/115698/1/115698.pdf Soon, W. and Posmentier, E. and Baliunas, S. (2000) Climate hypersensitivity to solar forcing? Annales Geophysicae, 18 (5). pp. 583-588. ISSN 0992-7689; eISSN: 0992-7689 https://angeo.copernicus.org/articles/18/583/2000/ 10.1007/s00585-000-0583-z
spellingShingle Soon, W.
Posmentier, E.
Baliunas, S.
Climate hypersensitivity to solar forcing?
title Climate hypersensitivity to solar forcing?
title_full Climate hypersensitivity to solar forcing?
title_fullStr Climate hypersensitivity to solar forcing?
title_full_unstemmed Climate hypersensitivity to solar forcing?
title_short Climate hypersensitivity to solar forcing?
title_sort climate hypersensitivity to solar forcing?
url http://psasir.upm.edu.my/id/eprint/115698/
http://psasir.upm.edu.my/id/eprint/115698/
http://psasir.upm.edu.my/id/eprint/115698/
http://psasir.upm.edu.my/id/eprint/115698/1/115698.pdf