Temperature and salinity are essential thermodynamic properties of sea ice. A 40-day long field campaign was carried out in winter 2020/2021 in the northern Bohai Sea in the landfast sea ice to investigate the seasonal sea ice temperature and salinity evolution. Ice thickness was measured routinely. A thermistor string was used to measure the ice temperature. Ice samples were collected for salinity by coring () and crumbing () methods. The mean vertical values of and were 4.8–5.8 psu and 8.3–13.8 psu, respectively. In cold ice, and were very close to each other. When ice temperature increased to −5 °C, and tended to differ from each other, and the difference was at largest at ice bottom. The brine volume fraction (BVF) ranged between 0.03 and 0.21 for and 0.03 and 0.32 for The growth of ice reached a maximum of 3.7 cm/day in very cold conditions, while the average growth rate was 0.8 cm/day comparable to other seasonally ice-covered seas. A numerical sea ice thermodynamic model was applied to simulate the ice thickness with particular attention to the effect of and on the ice mass balance. The modeled overall ice growth rate was 0.7 cm/day and agreed well with the observations but during cold periods the simulation was biased down (1.1 cm/day); a possible reason is underestimation of the thermal conductivity in the model. The modeled ice thickness differed by 3 cm when using and as the input salinity profiles indicating that salinity has a minor impact on sea ice mass balance during mid-winter.

中文翻译：

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渤海陆地冰的温度和盐度：观测和模拟

温度和盐度是海冰的基本热力学特性。 2020/2021年冬季，在渤海北部的陆地海冰中开展了为期40天的野外调查，以调查季节性海冰温度和盐度演变。常规测量冰厚度。使用热敏电阻串来测量冰的温度。通过取芯（）和碎屑（）方法收集冰样本的盐度。和 的平均垂直值分别为 4.8–5.8 psu 和 8.3–13.8 psu。冰冷的冰天雪地里，彼此的距离很近。当冰温升高到-5℃时，冰温之间存在差异，且差异在冰底最大。盐水体积分数 (BVF) 范围为 0.03 至 0.21 和 0.03 至 0.32 冰生长在极冷条件下达到最大 3.7 厘米/天，而与其他季节性冰相比，平均生长率为 0.8 厘米/天- 覆盖海洋。应用数值海冰热力学模型来模拟冰厚度，特别关注冰质量平衡的影响。模拟的整体冰生长率为 0.7 厘米/天，与观测结果吻合良好，但在寒冷时期，模拟出现偏差（1.1 厘米/天）；一个可能的原因是低估了模型中的热导率。当使用 和 作为输入盐度剖面时，建模的冰厚度相差 3 厘米，这表明盐度对仲冬期间的海冰质量平衡影响较小。