Abstract

The study of winter seasonal predictability with the climate model INM-CM5-0 is presented. Initial conditions were produced using ERA-Interim reanalysis data for atmosphere, SODA3.4.2 reanalysis data for ocean and the bias-correction algorithm. The seasonal 5-month re-forecasts consisting of 10 ensemble members with small initial condition perturbations for each year over the 35-yr period are conducted. A comparison of the multiyear mean winter averaged anomaly correlation for basic variables in several regions with similar results of SLAV model was conducted. An increase in the anomaly correlation for the years with El Niño and La Niña events was shown. The predictability of NAO and PNA indices was studied. INM-CM5-0 provides very high skill in predicting the winter NAO (correlation coefficient of 0.71 with ERA-Interim reanalysis and 0.68 with instrumental CRU data for 1991–2010). It was shown, that the stratospheric variability provides a significant contribution, although potentially is not the only cause of model high skill in NAO index predictability. Correlation coefficients for PNA index in December-February is 0.60. In the years of the most pronounced El Niño the values of PNA index have significantly positive values, and for La Niña years they are noticeably less than zero.

摘要

提出了使用气候模型INM-CM5-0进行冬季季节性可预测性的研究。初始条件是使用ERA-Interim大气再分析数据，SODA3.4.2海洋再分析数据和偏差校正算法产生的。在35年的期间内，每年进行10个合奏成员组成的季节性5个月重新预测，每年的初始条件扰动很小。对多个地区基本变量的多年平均冬季平均异常相关性进行了比较，结果与SLAV模型的结果相似。随着厄尔尼诺事件和拉尼娜事件的发生，近年来异常相关性有所增加。研究了NAO和PNA指数的可预测性。INM-CM5-0在预测冬季NAO方面提供了非常高的技巧（ERA-Interim重新分析的相关系数为0.71，相关系数为0。68含1991–2010年的仪器CRU数据）。结果表明，平流层的变化提供了重要的贡献，尽管可能不是NAO指数可预测性模型高技能的唯一原因。12月至2月PNA指数的相关系数为0.60。在厄尔尼诺现象最为明显的年份，PNA指数的值具有明显的正值，而在拉尼娜年份，则明显小于零。