Representation of Synoptic‐Scale Rossby Wave Packets and Blocking in the S2S Prediction Project Database
Representation of Synoptic‐Scale Rossby Wave Packets and Blocking in the S2S Prediction Project Database
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DOI：
10.1029/2018gl081381
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发表时间：
2019-01
影响因子：
5.2
通讯作者：
J. Quinting;F. Vitart
中科院分区：
文献类型：
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作者：
J. Quinting;F. Vitart
罗斯比波包（RWPs）是主要的中纬度大气现象之一。rwp的现实表示对于熟练地预测每天的天气及其极端天气是必不可少的。利用客观的RWP跟踪技术，验证了亚季节到季节（S2S）预测项目数据库中所有模型的RWP表示。与重新分析一致，重新预测显示每4天有一个RWP。由于大西洋-欧洲扇区的负RWP衰减频率偏差，具有最粗网格间距的三个模型倾向于高估传播距离。对大气阻塞的验证表明，这种偏置与同一区域的负阻塞频率偏置有关。在网格间距较细的模型中，偏差减小。然而，这种偏置减少不仅取决于网格间距，这突出了关键物理过程的不同表示对rwp和阻塞的影响。
Rossby wave packets (RWPs) are one of the dominating midlatitude atmospheric phenomena. A realistic representation of RWPs is essential for a skillful prediction of the day‐to‐day weather and its extremes. Using an objective RWP tracking technique, this study verifies the representation of RWPs for all models in the Subseasonal to Seasonal (S2S) Prediction Project Database. Consistent with reanalyses, the reforecasts show one RWP every 4 days. The three models with the coarsest grid spacing tend to overestimate the propagation distance due to a negative RWP decay frequency bias over the Atlantic‐European sector. A verification of atmospheric blocking suggests that this bias is related to a negative blocking frequency bias in the same region. The biases are reduced in models with finer grid spacing. However, that this bias reduction is not only dependent on the grid spacing highlights the effect of the different representation of key physical processes on RWPs and blocking.