COMPARISON RESEARCH OF ENKF AND PARTICLE FILTER IN A SIMPLE MODEL
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摘要: 集合卡尔曼滤波和粒子滤波是大气海洋领域两种先进的数据同化方法。理论上讲,粒子滤波克服了集合卡尔曼滤波中先验分布的高斯假定。但现有的关于两种方法的比较研究不够全面和系统,基于简单的洛伦兹63模式,重点对基于确定性集合卡尔曼滤波和均权重粒子滤波的数据同化方法开展对比分析,通过对观测误差和模式误差的不同配置,设计了四组试验着重研究两种方法相同试验条件下的同化效果。试验结果表明:与采用最优膨胀系数的集合卡尔曼滤波的同化方法相比,均权重粒子滤波的均方根误差更加依赖于观测信息的质量,但最优膨胀因子的集合卡尔曼滤波的均方根误差低于粒子滤波同化方法。Abstract: The Ensemble Kalman Filter (EnKF) and Particle Filter (PF) are two kinds of advanced data assimilation methods in the atmospheric and oceanic research. Theoretically, the PF overcomes the Gaussian assumption of the priori distribution in EnKF. But up to now comparison and research on them are incomplete and unsystematic. Based on the Lorenz-63 model and different settings of the observational and model errors, this paper designed four sets of experiments to analyze and compare one kind of deterministic EnKF with the equal-weight PF. The results show that the RMSEs of the EnKF with the optimallyinflatedfactor are lower while those of the equal-weight PF are more dependent on the observation quality.
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Key words:
- atmospheric environment /
- data assimilation /
- EnKF /
- equal-weight particle filter
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表 1 四组试验设置
试验 σ ρ β 观测误差 试验1 9.95 28 8/3 无 试验2 9.95 28 8/3 有 试验3 9.95+白噪声 28+白噪声 8/3+白噪声 无 试验4 9.95+白噪声 28+白噪声 8/3+白噪声 有 -
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