海洋环流模式对平流方案与分辨率的敏感性
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海洋环流模式对平流方案与分辨率的敏感性

肖 潺 1,2 俞永强 1 吴方华 1,2 刘海龙 1

1. 中国科学院大气物理研究所大气科学和地球流体力学数值模拟国家重点实验室(LASG), 北京, 100029

2. 中国气象局国家气候中心, 北京, 100081

摘 要

文中将中国科学院大气物理研究所大气科学和地球流体力学数值模拟国家重点实验室(LASG )发展的准全球海洋环流模式(LICOM ),从水平分辨率、垂直分辨率、平流方案3个方面分别采用不同的方案,进行组合试验,研究这些因素对于海洋环流(特别是热带海洋)的重要影响。8组试验表明,水平分辨率的提高,对于流场的改进有显著作用,能够使流场达到与实际非常接近的强度;调整的垂直分辨率,上层海洋的加密,能够使热带太平洋上层海洋的模拟改进;引入的两步保形平流方案,能够使得热带太平洋海温的模拟有所改进,这种改进的效果在低分辨率的情况下,尤为明显。同时,8组试验也一致地表现出等温线的密集程度比实际情况稀疏,这反映了模式在物理过程,特别是混合过程的描述方面,还有值得改进的地方。

关键词:水平分辨率, 垂直分辨率, 两步保形平流方案, 热带太平洋冷舌

中图法分类号 P47

资助课题:国家自然科学基金项目 (40221503和40675049) 、科技部重点基础研究计划(2007CB411806)和中国科学院创新团队国际合作伙伴计划“气候系统模式的研发和应用”。 作者简介:肖潺,主要从事气候数值模拟。Email:xiaochan@cma.gov.cn

2007-07-12收稿,2007-12-29改回.

An oceanic general circulation model's sensitivity to advection schemes and spatial resolution.

XIAO Chan 1,2 YU Yongqiang 1 WU Fanghua 1,2 LIU Hailong 1

1. State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics (LASG), Institute of Atmospheric Physics,Beijing 100029, China

2. National Climate Center, China Meteorological Administration, Beijing 100081, China Xiao Chan, Yu Yongqiang, Wu Fanghua, Liu Hailong.2008.

Abstract

Based on an eddy permitting, quasi -global oceanic general circulation model, LICOM (LASG/IAP(State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics, Institute of Atmospheric Physics) Climate System Ocean Model), the influences of the horizontal, vertical resolution and advection scheme on the tropical ocean circulation are investigated. Eight sensitivity experiments suggest that (1) higher horizontal resolution results in enhanced currents in the tropical Pacific Ocean, which are closer to the observation than those from experiments with lower horizontal resolution; (2) experiments with finer vertical resolution reveal reasonable vertical structure in the upper tropical ocean; (3) the two -step shape preserving advection scheme makes better simulation of sea surface temperature in the upper ocean, especially in experiments with lower horizontal resolution. However, all experiments show sparser isotherms than the observation, which implies that the physical parameterization of the ocean model still need to be improved, especially of the mixing process. Key words :Horizontal resolution, Vertical resolution, Two step Shape Preserving Advection Scheme(TSPAS), Cold tongue in the tropical Pacific Ocean