Thermodynamic process between the ice and the ocean plays a critical role in the evolution of sea-ice growth and melting in marginal seas. At the ice-ocean interface, the oceanic heat flux and the conductive heat flux transmitted through the ice layer jointly determine the latent heat flux driving the phase change (i.e., ice freezing/melting). In this study, the determination of two important thermal parameters in the ice module of the HAMSOM ice-ocean coupled model, namely the mixed layer thickness and the heat exchange coefficient at the ice-ocean interface, has been adjusted to improve the model performance. Spatio-temporal variations of heat fluxes at the ice-ocean interface in the Bohai Sea are investigated, based on the validated sea ice simulation in the 2011/2012 ice season. The relationships between the interfacial heat fluxes and oceanic and atmospheric conditioning factors are identified. We found that the surface conductive heat flux through ice shows short-term fluctuations corresponding to the atmospheric conditions, the magnitude of these fluctuations decreases with depth in the ice layer, likely due to reduced influence from atmospheric conditions at greater depths. Atmospheric conditions are the key controlling factors of the conductive heat flux through ice, while the oceanic heat flux is mainly controlled by the oceanic conditions (i.e., mixed layer temperature). Spatially, the value of the oceanic heat flux is larger in the marginal ice zone with relatively thin ice than in the inner ice zone with relatively thick ice. In the Bohai Sea, when ice is growing, heat within the ice layer is transferred upward from the ice base, and the heat is losing at the ice-ocean interface. This heat loss in the inner ice zone is obviously greater than that in the marginal ice zone. Whereas when ice is melting, the opposite is true.

中文翻译：

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渤海冰海界面热通量的时空变化


冰和海洋之间的热力学过程在边缘海冰生长和融化的演变中起着关键作用。在冰-海洋界面处，海洋热通量和通过冰层传递的传导热通量共同决定了驱动相变（即冰冻结/融化）的潜热通量。在本研究中，调整了 HAMSOM 冰-海耦合模型冰模块中两个重要热参数的确定，即混合层厚度和冰-海洋界面处的热交换系数，以提高模型性能。基于 2011/2012 年冰季经过验证的海冰模拟，研究了渤海冰海界面热通量的时空变化。确定了界面热通量与海洋和大气条件因子之间的关系。我们发现，通过冰的表面传导热通量显示出与大气条件相对应的短期波动，这些波动的大小随着冰层的深度而减小，这可能是由于更深处大气条件的影响减小。大气条件是大气条件通过冰的传导热通量的关键控制因素，而海洋热通量主要受海洋条件（即混合层温度）控制。在空间上，在相对较薄的边缘冰区，海洋热通量的值比在相对较厚的内冰区中要大。在渤海，当冰层增长时，冰层内的热量从冰底向上传递，热量在冰海界面处流失。 内冰区的这种热损失明显大于边缘冰区的热量损失。而当冰融化时，情况恰恰相反。