Spatially variable drag in the shear-controlled melt parameterisation below ice shelves in NEMO ...

• Main Authors: Vallot, Dorothée, Jourdain, Nicolas, Mathiot, Pierre
• Format: Conference Object
• Language: unknown
• Published: GFZ German Research Centre for Geosciences 2023
• Subjects: Amundsen Sea; Ice Shelf; Ice Shelves
• Online Access: https://dx.doi.org/10.57757/iugg23-2515; https://gfzpublic.gfz-potsdam.de/pubman/item/item_5019373

<!--!introduction!--> Currently, in NEMO and in most ocean models, melting parameterisation below ice shelves is controlled by shear stress, which depends on the mean flow in the boundary layer and the so-called coefficient of drag. This parameter, constant in space and time, is usually tuned to approach observed melt at a given ice shelf. This is equivalent to parameterise ice shelf bottoms as smooth surfaces, whereas, in reality, they can be very rough at different scales. As ice shelves are predicted to experience further damage in the future, applying a spatially varying drag might decrease uncertainties related to melt predictions below ice shelves. Here we present a study with a spatially variable coefficient of drag, which depends on the topography and on the first wet cell height. We use the ice shelf parameterisation of NEMO4.2 on a configuration of Amundsen Sea at 12 th of a degree. ... : The 28th IUGG General Assembly (IUGG2023) (Berlin 2023) ...