Twin 5-month seasonal forecast experiments are performed to predict the September 2018 mean and minimum ice extent using the fully coupled Navy Earth System Prediction Capability (ESPC). In the control run, ensemble forecasts are initialized from the operational US Navy Global Ocean Forecasting System (GOFS) 3.1 but do not assimilate ice thickness data. Another set of forecasts are initialized from the same GOFS 3.1 fields but with sea ice thickness derived from CryoSat-2 (CS2). The Navy ESPC ensemble mean September 2018 minimum sea ice extent initialized with GOFS 3.1 ice thickness was over-predicted by 0.68 M km2 (5.27 M km2) vs the ensemble forecasts initialized with CS2 ice thickness that had an error of 0.40 M km2 (4.99 M km2), a 43% reduction in error. The September mean integrated ice edge error shows a 18% improvement for the Pan-Arctic with the CS2 data vs the control forecasts. Comparison against upward looking sonar ice thickness in the Beaufort Sea reveals a lower bias and RMSE with the CS2 forecasts at all three moorings. Ice concentration at these locations is also improved, but neither set of forecasts show ice free conditions as observed at moorings A and D.

中文翻译：

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分析 CryoSat-2 冰层厚度初始化对北极海冰季节性预测的影响

使用完全耦合的海军地球系统预测能力 (ESPC) 进行了为期 5 个月的双季预报实验，以预测 2018 年 9 月的平均和最小冰层范围。在控制运行中，集合预报从可操作的美国海军全球海洋预报系统 (GOFS) 3.1 初始化，但不吸收冰层厚度数据。另一组预测是从相同的 GOFS 3.1 字段初始化的，但海冰厚度来自 CryoSat-2 (CS2)。海军 ESPC 集合平均 2018 年 9 月用 GOFS 3.1 冰层厚度初始化的最小海冰范围被高估了 0.68 M km2（5.27 万公里2) 与以 CS2 冰厚度初始化的集合预报相比，其误差为 0.40 M km2（499 万公里2)，误差减少了 43%。9 月平均综合冰缘误差显示，使用 CS2 数据与对照预测相比，泛北极地区的改善率为 18%。与波弗特海向上看的声纳冰层厚度的比较显示，在所有三个系泊处，CS2 预测的偏差和 RMSE 都较低。这些位置的冰浓度也有所改善，但两组预测均未显示在停泊处 A 和 D 观察到的无冰条件。