Investigating the Effects of Salinity and Turbulence on Ice Melt

Glacial melt across the world is accelerating, contributing to sea level rise (SLR). To effectively mitigate and adapt to the impacts of SLR, it is necessary that glacial melt models accurately predict SLR rates. However, a growing body of research has shown that current glacial melt models are severely underpredicting melt rates, largely due to a lack of consensus regarding how to incorporate turbulence generated by melt plumes, subglacial discharge, and other dynamic flows (Sutherland, 2019; Jackson, 2020).

To improve our understanding of the fundamental relationships between turbulence at the ice-ocean interface and submarine melting, we have performed laboratory experiments in which ice was melted in a facility with specified water temperature, salinity, and ambient turbulence. We expand on previous work conducted in freshwater through comparison with our results in saline water, finding that melt rates increased significantly under saline conditions, interacting nonlinearly with the effects of turbulence (McCutchan et al, 2024). In addition measurements of melting from dyed ice spheres allow us to identify melt events as a function of turbulence, including exceedance of critical friction velocities, dissipation levels, and other flow features. The parameterizations we are developing through this study will directly inform the transfer coefficients that feed glacier melt models to accurately account for the dynamics of ice-ocean environments and improve ice loss predictions.