TY - JOUR
T1 - Fully Developed Superrotation Driven by the Mean Meridional Circulation in a Venus GCM
AU - Sugimoto, Norihiko
AU - Takagi, Masahiro
AU - Matsuda, Yoshihisa
N1 - Funding Information:
This study was conducted under the joint research project of the Earth Simulator Center with title “Simulations of atmospheric general circulations of Earth‐like planets by AFES”. The work is partly supported by MEXT | Japan Society for the Promotion of Science (JSPS) grants JP16H02225, JP16H02231, and JP17H02961 and Kyoto Sangyo University Research Grants. The GFD‐ DENNOU Library was used for creating figures. The authors thank Dr. Sebastien Lebonnois for careful reviews. Results from the GCM simulations performed in this paper are provided as supporting information.
Publisher Copyright:
©2019. American Geophysical Union. All Rights Reserved.
PY - 2019/2/16
Y1 - 2019/2/16
N2 - Fully developed superrotation is reproduced for the first time in very long term simulations with a dynamical Venus general circulation model (GCM) driven by a zonally averaged component of the realistic solar heating only. Starting from a motionless state with temperature distribution including a low static stability layer in the lower cloud layer, the fast superrotating zonal flow of ~100 m/s is established after 500 Earth years. In this experiment, the mean meridional circulation is responsible for generating the superrotation, because effects of thermal tides, topography, radiation process, and cloud physics are excluded in the present simulations. Sensitivity experiments indicate that the vertical eddy viscosity smaller than 0.02 m 2 /s is necessary for the fast superrotation to appear. The low static stability layer also strongly affects the superrotation with high-latitude jets through angular momentum transport by baroclinic/barotropic instability in the cloud layer.
AB - Fully developed superrotation is reproduced for the first time in very long term simulations with a dynamical Venus general circulation model (GCM) driven by a zonally averaged component of the realistic solar heating only. Starting from a motionless state with temperature distribution including a low static stability layer in the lower cloud layer, the fast superrotating zonal flow of ~100 m/s is established after 500 Earth years. In this experiment, the mean meridional circulation is responsible for generating the superrotation, because effects of thermal tides, topography, radiation process, and cloud physics are excluded in the present simulations. Sensitivity experiments indicate that the vertical eddy viscosity smaller than 0.02 m 2 /s is necessary for the fast superrotation to appear. The low static stability layer also strongly affects the superrotation with high-latitude jets through angular momentum transport by baroclinic/barotropic instability in the cloud layer.
KW - GCM
KW - Venus atmosphere
KW - baroclinic instability
KW - mean meridional circulation
KW - superrotation
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U2 - 10.1029/2018GL080917
DO - 10.1029/2018GL080917
M3 - Article
AN - SCOPUS:85061343349
VL - 46
SP - 1776
EP - 1784
JO - Geophysical Research Letters
JF - Geophysical Research Letters
SN - 0094-8276
IS - 3
ER -