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    | Titel | Tropical cirrus and water vapor: an effective Earth infrared iris feedback? |  
    | VerfasserIn | Q. Fu, M. Baker, D. L. Hartmann |  
    | Medientyp | Artikel 
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    | Sprache | Englisch 
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    | ISSN | 1680-7316 
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    | Digitales Dokument | URL |  
    | Erschienen | In: Atmospheric Chemistry and Physics ; 2, no. 1 ; Nr. 2, no. 1 (2002-01-30), S.31-37 |  
    | Datensatznummer | 250000369 
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    | Publikation (Nr.) |  copernicus.org/acp-2-31-2002.pdf |  
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        | Zusammenfassung |  
        | We revisit a model of feedback processes proposed by Lindzen et
      al. (2001), in which an assumed 22% reduction in the area of tropical high clouds per degree increase in sea
      surface temperature produces negative feedbacks associated with upper tropospheric
      water vapor and cloud radiative effects.  We argue that the water vapor feedback is
      overestimated in Lindzen et al. (2001) by at least 60%, and that the high cloud feedback is small.
      Although not mentioned by Lindzen et al. (2001), tropical low clouds make a significant
      contribution to their negative feedback, which is also overestimated.  Using more realistic
      parameters in the model of Lindzen et al. (2001), we obtain a feedback factor in the range of
      -0.15 to -0.51, compared to their larger negative feedback factor of -0.45 to
      -1.03.  It is noted that our feedback factor could still be overestimated due to the assumption of
      constant low cloud cover in the simple radiative-convective model. |  
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