A Comparison Study of Tropical Pacific Ocean State Estimation： Low-Resolution Assimilation vs. High-Resolution Simulation

• Published in: Advances in atmospheric sciences Vol. 22; no. 2; pp. 212 - 219
• Main Author: 符伟伟 朱江 周广庆 王会军
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Nature B.V 01.03.2005; Graduate School of the Chinese Academy of Sciences, Beijing 100039%Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029; Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029
• Subjects: Data collection; Simulation; 低度解模型; 热带太平洋地区; 状态评估; 计算机模拟; high-resolution model; comparison study; data assimilation; low-resolution model
• ISSN: 0256-1530; 1861-9533
• DOI: 10.1007/BF02918510

A comparison study is performed to contrast the improvements in the tropical Pacific oceanic state of a low-resolution model respectively via data assimilation and by an increase in horizontal resolution.A low resolution model (LR) (1°lat by 2°lon) and a high-resolution model (HR) (0.5°lat by 0.5°lon) are employed for the comparison. The authors perform 20-yr numerical experiments and analyze the annual mean fields of temperature and salinity. The results indicate that the low-resolution model with data assimilation behaves better than the high-resolution model in the estimation of ocean large-scale features.From 1990 to 2000, the average of HR's RMSE (root-mean-square error) relative to independent Tropical Atmosphere Ocean project (TAO) mooring data at randomly selected points is 0.97℃ compared to a RMSE of 0.56℃ for LR with temperature assimilation. Moreover， the LR with data assimilation is more frugal in computation. Although there is room to improve the high-resolution model， the low-resolutionm odel with data assimilation may be an advisable choice in achieving a more realistic large-scale state of the ocean at the limited level of information provided by the current observational system.