Coastal fast ice in the Shokalski Strait

Abstract

Field investigations of coastal fast ice near the research station Ice Base on the «Cape Baranova», carried out in 2013–2014, made possible to reveal a number of characteristics of the sea ice cover formation. It has been shown that during winter and early spring the sea ice thickness, being formed due to intensive snow drift and caused by that flooding of the ice cover just near the coast of the Bolshevik Island, substantially grows at its upper boundary, that is typical for the Antarctic seas. At the same time, similar process of the ice growth at a relatively short distance from the coast shows all features characteristic for the ice cover in the Arctic seas, and that is well reproduced by the conceptual numerical sea ice model. Thus, the region of the Ice Base «Cape Baranova» represents a natural laboratory for studying the processes of the sea ice formation in both, the Arctic and Antarctic seas under condition of the same atmospheric forcing. Transformation of the fast ice structure during the summer time is described. Results of the investigations has demonstrated that despite the radical changes in the structure thicknesses of the fast ice remained almost unchanged due to the ice growth on the bottom boundary of the ice cover until a destruction of it in August.

Towards an advanced observation system for the marine Arctic in the framework of the Pan-Eurasian Experiment (PEEX)

“…Layers of granular ice, formed due to refreezing of flooded or partly melted snowpack, on top of columnar ice may be detected using mass-balance buoy data supported by thermodynamic modelling (Cheng et al, 2014). Such layers may become more common due to thinning sea ice and increasing precipitation, favouring heavier snow load on top of thin ice, which increases the occurrence of flooding (Borodkin et al, 2016;Granskog et al, 2017). Under present conditions of decreased ice concentration and thickness, the influence of the ocean heat on the ice cover is increasing, providing positive feedback on a seasonal timescale (Ivanov et al, 2016).…”

“…Tides contribute to the mixing of water masses, further affecting sea ice melt (Luneva et al, 2015) and the thermohaline circulation with potential impacts on the Arctic and global climate (Holloway and Proshutinsky, 2007). Other small-scale processes important for climate include the exchange of momentum, heat, and salt at the ice-ocean interface, brine formation (Bourgain and Gascard, 2011), diapycnal mixing (Rainville et al, 2011), double diffusive convection (Sirevaag and Fer, 2012), and (sub-)mesoscale eddies and fronts (Timmermans et al, 2012).…”

Response to the comments by Referee 2

“…Layers of granular ice, formed due to refreezing of flooded or partly melted snowpack, on top of columnar ice may be detected using mass-balance buoy data supported by thermodynamic modelling (Cheng et al, 2014). Such layers may become more common due to thinning sea ice and increasing precipitation, favouring heavier snow load on top of thin ice, which increases the occurrence of flooding (Borodkin et al, 2016;Granskog et al, 2017). Under present conditions of decreased ice concentration and thickness, the influence of the ocean heat on the ice cover is increasing, providing positive feedback on a seasonal timescale (Ivanov et al, 2016).…”