The form drag on sea ice ridge plays an important role in ice-ocean momentum exchange and determines the drift of sea ice. This paper presents a study on the water drag force on ridge keels of sea ice through both physical and numerical simulations. Tests comprising of six slope angles (α) of ridge keel, five keel depths (h), and twelve flow velocities (u) have been conducted, and the physical modelling results agree well with the numerical simulations. The results reveal that the drag force on ridge keel increases with increasing α, h, and u. The impact of the size of the tank on ice-water drag force is discussed, and size-free results are obtained through numerical simulations. The form drag coefficient on ridge keel nearly has nothing to do with u and h, but obviously increases with α. A parameterization of the drag coefficient is proposed as C = 0.315×ln(α) − 0.616, which is potential to be applied to full scale sea ice in the polar regions
Climate warming is an important distinct trend of global climate. Global warming is amplified in Arctic and is called Arctic amplification (Screen and Francis, 2016). As the most important feature of polar regions, sea ice has an important influence on atmospheric circulation, ocean circulation and global climate. In recent years, the rapid changes in Arctic sea ice on northern hemisphere weather becomes more and more obvious, so the research on the change of Arctic sea ice is also becoming increasingly important (Stephenson and Pincus, 2017). Among the research methods on polar sea ice, numerical simulation is becoming one of the important means. Ice dynamics describes the interaction between flow and the sea ice, also between atmosphere and the sea ice, when the interaction between flow and sea ice, the drag coefficient is an important factor in determining the flow drag force, and the parameterization on the drag coefficient has been gradually developed (Tsamados et al., 2014).
