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For the warmest period from 15 to 17 April significant anomalies could be seen over the North Pole in the figure above. They seem more pronounced for the 2-metre temperature compared to T at 850 hPa. Significant positive anomaly can be noticed over Europe form the Mediterranean up to England and Germany caused by warm advection from North Africa. It also appears to be quite cold for the season over Africa. All the anomalies displayed are calculated from ECMWF analysis versus ERA-Interim.
The plot above shows the SST anomaly and sea-ice cover for the 17 April. The normal sea-ice cover is inside the purple line. West of Svalbard the SSTs are somewhat warmer than normal but the sea-ice cover was almost normal.
3. Predictability
3.1 Data assimilation
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