on the radiative and dynamical feedbacks over the equatorial pacific cold tongue de-zheng sun john...
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On the Radiative and Dynamical Feedbacks over the Equatorial Pacific Cold Tongu
e
De-Zheng SunJohn Fasullo
Tao ZhangAndres Roubicek
J. Climate, 2003, Vol. 16, 2425-2432
冷舌
2121
The equatorial cold tongue
Walker Circulation
Solar radiation
Outgoing Longwave Radiation
Surface heat flux into the ocean
Net radiative flux
S: the net solar radiation Sc: the clear-sky solar radiation Cs: the shortwave forcing of clouds
F: the outgoing longwave radiation E: the surface emission G: the total greenhouse effect Ga: the greenhouse effect of water vapor Cl: the greenhouse effect of clouds
Da: the vertically integrated, horizontal convergence of total energy
Fs: the net surface heat flux into the ocean
The model data of CCM3 VS the Earth Radiation Budget Experiment(ERBE)
2121
The equatorial cold tongue
SST
Anomaly
The greenhouse effect of water vapor
Da
Observation
Model
Observation
Model
Cs
Cl
El Nino warming
La Nina cooling JAN JAN JAN JAN
1986 1987 1988 1989
0
1
-1
高雲
低雲
中雲
觀測 模式
相加
觀測
模式
The results show that
• the net atmospheric feedback in the CCM3 over the equatorial Pacific cold tongue region is strongly positive
(5.1 W M-2K-1),
while the net atmospheric feedback in the real atmosphere is strongly negative
(-6.4 W M-2K-1).
This discrepancy is largely due to errors in cloud feedbacks
• The positive feedback from the greenhouse effect of clouds in the model is significantly larger than the observed,
• while the negative feedback from the solar forcing of clouds in the model is significantly weaker.