The Aqua-Planet Experiment (APE): CONTROL SST Simulation

Journal of the Meteorological Society of Japan. Ser. II

Hartmut BORTH^1,15  Peter BECHTOLD¹³  Masaki SATOH^2,20  Hisashi NAKAMURA⁴  Kensuke NAKAJIMA^1,16  Yimin LIU^2,21  Andrea MOLOD²²  Akio KITOH^1,14  David L. WILLIAMSON^1,6  Michael BLACKBURN¹  Masahiro WATANABE^2,20  Kavirajan RAJENDRAN²  Yoshiyuki O. TAKAHASHI^1,7  Volkmar WIRTH^1,12  Wataru OHFUCHI^1,9  Masaki ISHIWATARI¹¹  Max J. SUAREZ²²  Helmut FRANK^1,18  Isaac M. HELD³  Ming ZHAO³  Myong-In LEE¹⁷  Hirofumi TOMITA^1,10  Masahide KIMOTO^2,20  John L. McGREGOR⁵  Rachel STRATTON^2,19  Yoshi-Yuki HAYASHI^1,7  Zaizhi WANG^1,8  Nils P. WEDI¹³ 

[1] National Centre for Atmospheric Science, University of Reading, Reading, UK;Center for Mathematical Modelling and Computer Simulation, National Aerospace Laboratories, Bangalore, India;Geophysical Fluid Dynamics Laboratory, Princeton University, Princeton, New Jersey, USA;Research Center for Advanced Science and Technology, The University of Tokyo, Tokyo, Japan;CSIRO Marine and Atmospheric Research, Aspendale, Australia;National Center for Atmospheric Research, Boulder, Colorado, USA;Center for Planetary Science, Kobe, Japan;National Climate Center, China Meteorological Administration, Beijing, China;Japan Agency for Marine-Earth Science and Technology, Yokohama, Japan;Advanced Institute for Computational Science, RIKEN, Kobe, Japan;Graduate School of Science, Hokkaido University, Sapporo, Japan;Institute for Atmospheric Physics, University of Mainz, Mainz, Germany;European Centre for Medium-Range Weather Forecasts, Reading, Berkshire, UK;Meteorological Research Institute, Tsukuba, Japan;Theoretical Meteorology, University of Hamburg, Hamburg, Germany;Faculty of Sciences, Kyushu University, Fukuoka, Japan;Ulsan National Institute of Science and Technology, Ulsan, Korea;Research and Development, Deutscher Wetterdienst, Offenbach, Germany;Met Office, Exeter, UK;Atmosphere and Ocean Research Institute, The University of Tokyo, Kashiwa, Japan;State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics, Institute of Atmospheric Physics, CAS, Beijing, China;Global Modeling and Assimilation Office, NASA Goddard Space Flight Center, Greenbelt, Maryland, USA

关键词: comparison of atmospheric general circulation models (GCMs);    idealized model configuration;    global energy buget;    tropical wave spectrum;    precipitation;   

DOI  :  10.2151/jmsj.2013-A02

学科分类：大气科学

来源: Meteorological Society of Japan

【 摘 要 】

Climate simulations by 16 atmospheric general circulation models (AGCMs) are compared on an aqua-planet, a water-covered Earth with prescribed sea surface temperature varying only in latitude. The idealised configuration is designed to expose differences in the circulation simulated by different models. Basic features of the aqua-planet climate are characterised by comparison with Earth.The models display a wide range of behaviour. The balanced component of the tropospheric mean flow, and mid-latitude eddy covariances subject to budget constraints, vary relatively little among the models. In contrast, differences in damping in the dynamical core strongly influence transient eddy amplitudes. Historical uncertainty in modelled lower stratospheric temperatures persists in APE.Aspects of the circulation generated more directly by interactions between the resolved fluid dynamics and parameterized moist processes vary greatly. The tropical Hadley circulation forms either a single or double inter-tropical convergence zone (ITCZ) at the equator, with large variations in mean precipitation. The equatorial wave spectrum shows a wide range of precipitation intensity and propagation characteristics. Kelvin mode-like eastward propagation with remarkably constant phase speed dominates in most models. Westward propagation, less dispersive than the equatorial Rossby modes, dominates in a few models or occurs within an eastward propagating envelope in others. The mean structure of the ITCZ is related to precipitation variability, consistent with previous studies.The aqua-planet global energy balance is unknown but the models produce a surprisingly large range of top of atmosphere global net flux, dominated by differences in shortwave reflection by clouds. A number of newly developed models, not optimised for Earth climate, contribute to this. Possible reasons for differences in the optimised models are discussed.The aqua-planet configuration is intended as one component of an experimental hierarchy used to evaluate AGCMs. This comparison does suggest that the range of model behaviour could be better understood and reduced in conjunction with Earth climate simulations. Controlled experimentation is required to explore individual model behaviour and investigate convergence of the aqua-planet climate with increasing resolution.

【 授权许可】

Unknown