The salinity of water and the slope of ice significantly influence the melt rate and surface morphology of ice, both highly relevant in the context of glacier and iceberg melting in oceanic environments. In this study, we conduct experiments on vertical and sloped ice blocks melting in quiescent saline water. Through the use of fringe projection profilometry, we measure the morphology of the ice's front face. In particular, we combine the spatiotemporal phase shifting and orthogonal sampling moire methods. The far field salinity in the experiments ranged from 0 g/kg to 35 g/kg, and angles are between $-{18}^{\circ }$ and ${50}^{\circ }$. The ice blocks are $L\times W\times H=12\mathrm{c}\mathrm{m}\times 23\mathrm{c}\mathrm{m}\times 32\mathrm{c}\mathrm{m}$ and submerged in water of approximately $20{}^{\circ }\mathrm{C}$, leading to $\text{Ra}=\mathcal{O}\left({10}^7\right)$. We identify and classify five surface morphologies and regimes arising from the flow regimes imposed by salinity and inclination, namely, scalloped, channelized, top-melting, bottom-melting, and incurved. The channelized morphology consists of vertical channels carved along the ice surface whose development originates from a Rayleigh-Bénard-type instability, and which are enhanced by bubbles released from the melting ice and rising along the interface. The scalloped regime is characterized by a rough dimpled pattern commonly referred to as scallops. We observe that increasing the salinity leads to scallops that are smaller, shallower, and more uniform in size. Additionally, a salinity dependence of the melt rate is found, showing a nonmonotonic behavior, while the inclination angle shows little influence on the overall melt rate.

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• Doubly diffusive convection
• Heat transfer
• Multiphase flows
• Phase transitions