Title: Investigating Surface Thickening and Snow Flooding for Arctic Sea Ice Restoration

All emissions pathways considered by the IPCC lead to an ice-free Arctic being likely by 2050 (https://doi.org/10.1038/s43017-023-00515-9) so we must take additional action if we are to prevent Arctic sea ice from disappearing. We are researching two proposed methods of thickening sea ice; the first, proposed by Desch et al., 2017 (https://doi.org/10.1002/2016EF000410), we call Surface Thickening. The idea behind Surface Thickening is to pump seawater through the sea ice and onto its surface to directly increase the thickness of the sea ice by the freezing of this seawater on the surface. The second, proposed by Pauling & Bitz, 2021 (https://doi.org/10.1029/2021EF002136), is Snow Flooding; the idea here is to flood snow with seawater thereby consolidating the highly insulating snow layer into more conductive ice, increasing the rate of natural freezing on the base of the sea ice and therefore thickening it.

Our research focuses on understanding the underlying physics governing each of the techniques and whether they are suitable for restoring sea ice. We begin with small scale modelling and lab experiments of freshwater flowing linearly and then radially over fresh ice. The models are analysed with respect to experimental data and aid our understanding of the underlying physics. We then investigate the impact of both Surface Thickening and Snow Flooding on ice growth statically in one dimension by comparing modelling based on simple assumptions and laboratory experiments in a cold room. We shall present new results from the modelling and experiments that further our knowledge on both techniques.