Combining a New Parameterization Scheme of Oceanic Heat Flux with Thickness Assimilation to Improve Sea Ice Forecast Accuracy in Liaodong Bay

Abstract

Liaodong Bay is one of the lowest latitude areas with seasonal sea ice cover in the Northern Hemisphere. Sea ice forecasting faces challenges in accuracy due to its low thickness. Therefore, a novel parameterization scheme for oceanic heat flux was developed to forecast sea ice thickness accurately. Application of the parameterization scheme for oceanic heat flux in the HIGHTSI model significantly improved the forecasting accuracy of sea ice thickness before the severe ice period. During this period, the RMSE of sea ice thickness measured on the JZ9–3 and the JZ20–2 oil platforms decreased by 0.53 cm and 2.90 cm compared to previous schemes, respectively. In order to improve the forecasting accuracy during the severe and melting ice periods, the observed and retrieved sea ice thickness was nudged into the model. The simulated results demonstrated a good agreement with monitored sea ice thickness distribution. During the entire season with sea ice cover, the R-squared values between simulated and retrieved sea ice thickness in the core area of Liaodong Bay reached 0.76. Furthermore, this study revealed a relatively strong correlation between air temperature and ice temperature on the following day. The proposed scheme provides a valuable approach to improve the forecasting accuracy for the areas with low thickness in the sea ice numerical models.

Keywords

• sea ice
• Liaodong Bay
• oceanic heat flux
• parameterization
• nudging