scholarly journals Improved Surface Layer Simulation Using Refined Vertical Resolution in the GFDL Atmospheric General Circulation Model

2019 ◽  
Vol 11 (4) ◽  
pp. 905-917
Author(s):  
Hyeyum Hailey Shin ◽  
Yi Ming ◽  
Ming Zhao ◽  
Xi Chen ◽  
Shian‐Jiann Lin
Keyword(s):  
Surface Layer ◽  
General Circulation Model ◽  
General Circulation ◽  
Atmospheric General Circulation Model ◽  
Circulation Model ◽  
Vertical Resolution ◽  
Atmospheric General Circulation

Simulating the QBO in an Atmospheric General Circulation Model: Sensitivity to Resolved and Parameterized Forcing

2016 ◽  
Vol 73 (4) ◽  
pp. 1649-1665 ◽  
Author(s):  
James A. Anstey ◽  
John F. Scinocca ◽  
Martin Keller
Keyword(s):  
Gravity Wave ◽  
General Circulation Model ◽  
General Circulation ◽  
Atmospheric General Circulation Model ◽  
Circulation Model ◽  
Wave Drag ◽  
Vertical Resolution ◽  
Atmospheric General Circulation ◽  
Downward Influence ◽  
Seasonal Synchronization

Abstract The quasi-biennial oscillation (QBO) of tropical stratospheric zonal winds is simulated in an atmospheric general circulation model and its sensitivity to model parameters is explored. Vertical resolution in the lower tropical stratosphere finer than ≈1 km and sufficiently strong forcing by parameterized nonorographic gravity wave drag are both required for the model to exhibit a QBO-like oscillation. Coarser vertical resolution yields oscillations that are seasonally synchronized and driven mainly by gravity wave drag. As vertical resolution increases, wave forcing in the tropical lower stratosphere increases and seasonal synchronization is disrupted, allowing quasi-biennial periodicity to emerge. Seasonal synchronization could result from the form of wave dissipation assumed in the gravity wave parameterization, which allows downward influence by semiannual oscillation (SAO) winds, whereas dissipation of resolved waves is consistent with radiative damping and no downward influence. Parameterized wave drag is nevertheless required to generate a realistic QBO, effectively acting to amplify the relatively weaker mean-flow forcing by resolved waves.

Sign in / Sign up

Export Citation Format

Share Document