Smoke and Pollution Aerosol Effect on Cloud Cover

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Smoke and Pollution Aerosol Effect on Cloud Cover

• Yoram J. Kaufman and Ilan Koren
• Science 313, 655 (2006)
• Sungho Kang
• Oct, 24, 2007
• ECI 289A Climate Change

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Contents

• Introduction
• Method
• Result and Discussion
• Limits
• Conclusion
• References

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Introduction
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Method
Sunphotometer

• Statistical Analysis
• AERONET
• - fc derived from eq 2(fc1-T0/T)
• - t (AOT or AOD)
• - tabs (AAT)
• MODIS
• - K (Top of Cloud)

Pyranometer
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Fig. 1. Global distribution of the AERONET
sunphotometers used in the analysis
Y. J. Kaufman et al., Science 313, 655 -658
(2006)
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Fig. 2. Scatterplots of the time interval between
two adjacent AERONET aerosol measurements that
were not obscured by clouds, as a function of the
average ttau around the interval
dfcidT/T
cloudiness
t
Y. J. Kaufman et al., Science 313, 655 -658
(2006)
tabs
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Fig. 3. Regional (A), seasonal (B), and Tc (C)
analyses of the AERONET data for the effect of
aerosols on cloud cover
?fci/?lnt(0.150.01)-(3.50.5)tabs
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Conclusion

• Cloud cover ,aerosol concentration (t)
• Cloud cover ,AAT ( tabs)
• ? fci/?lnt(0.17 0.01)-(3.5 0.5) tabs
• 25 of ? fci/?lnt associated with PWV
• Aerosol increase cloud cover up to 5

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Limitations

• Methodology
• Problem of statistical method
• -can not define specific cloud condition
• Limitation of AERONET
• -do not include extended cloud system
• -limited station sites

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References

• H. Yu et al, ACP(2006)-measurement based
  assessments of aerosol

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Question and Comment

• Thank you