Data of recent submission to Journal of Advances in Modeling Earth Systems (Data assimilation in a regional high-resolution ocean model by using Ensemble Adjustment Kalman Filter and its application during 2020 cold spell event over Asia-Pacific region, [Paper # 2022MS003199]).

Over the past several decades, cold spell events have increased, not only in duration and frequency, but also in intensity. It poses a great challenge to the capability of ocean numerical models. In this study, the multiple datasets are assimilated into a regional high-resolution ocean model to improve the modelling results during a strong cold spell event of 2020. To reduce the calculation cost, some effective strategies are designed in data assimilation. The overall error statistics of the sea surface elevation, temperature, salinity and velocity showed that the simulated results of all variables after assimilation had been improved with different degrees. Furthermore, the temporal evolutions of ocean state during 2020 cold spell event were better reproduced after data assimilation.
In conclusion, the data assimilation in this regional high-resolution ocean model has successfully reduced the model biases and the physical processes in reality can be well produced.