Stratification effects in the turbulent boundary layer beneath a melting ice shelf: Insights from resolved large-eddy simulations ...

• Main Authors: Vreugdenhil, CA, Taylor
• Format: Article in Journal/Newspaper
• Language: English
• Published: American Meteorological Society 2019
• Subjects: Ice shelves; Turbulence; Large eddy simulations; Ice Shelf; Ice Shelves
• Online Access: https://dx.doi.org/10.17863/cam.39552; https://www.repository.cam.ac.uk/handle/1810/292402

AbstractOcean turbulence contributes to the basal melting and dissolution of ice shelves by transporting heat and salt toward the ice. The meltwater causes a stable salinity stratification to form beneath the ice that suppresses turbulence. Here we use large-eddy simulations motivated by the ice shelf–ocean boundary layer (ISOBL) to examine the inherently linked processes of turbulence and stratification, and their influence on the melt rate. Our rectangular domain is bounded from above by the ice base where a dynamic melt condition is imposed. By varying the speed of the flow and the ambient temperature, we identify a fully turbulent, well-mixed regime and an intermittently turbulent, strongly stratified regime. The transition between regimes can be characterized by comparing the Obukhov length, which provides a measure of the distance away from the ice base where stratification begins to dominate the flow, to the viscous length scale of the interfacial sublayer. Upper limits on simulated turbulent transfer ...