Held-Hou model

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Transcript Held-Hou model

Mean Meridional Circulation
• Hadley cell theories
• Held-Hou model
• Ferrel cell
Hadley circulation theories
• Schneider (1977) zonally symmetric steady state model
• Held and Hou (1980), Lindzen and Hou (1988), Hou and
Lindzen (1992) included effects of distribution of heating
related to latent heat feedback, and displacement of upward
branch away from equator (summer, winter scenarios)
• Schneider (1987) and Emanuel (1995) included non-zonal
monsoonal effects
• Fang and Tung (1999) included time-varying heating that
enhanced strength of time mean.
• Theories successfully account for several features of Hadley
circulation:
Width of circulation, position of subtropical jet which are controlled
by geostrophy and conservation of heat and momentum
All use radiative-convective basic state, often with Newtonian
relaxation to produce heating and cooling.
일반화된 좌표계와 속도
발산과 와도
Held-Hou model
Held-Hou 2층 모형의 개요.
< 절대각운동량의 보존 >
< 복사평형 >
< 적도 부근 근사 >
이므로
< 온도풍 균형 >
복사평형온도와 실제의 온도
Held-Hou 모형에서 구한 zonal wind의 위도에 따른 변화
< Held-Hou 모형에서 해들리 순환의 세기 >
전형적인 수평속도의 규모를 식으로 부터 추정하면