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1. Direct Observations of Wave‐Sea Ice Interactions in the Antarctic Marginal Ice Zone

   https://doi.org/10.1029/2023JC019948  

   Wahlgren, S; Thomson, J; Biddle, L C; Swart, S (October 2023, Journal of Geophysical Research: Oceans)

   Abstract Wave energy propagating into the Antarctic marginal ice zone effects the quality and extent of the sea ice, and wave propagation is therefore an important factor for understanding and predicting changes in sea ice cover. Wave‐sea ice interactions are notoriously hard to model and in situ observations of wave activity in the Antarctic marginal ice zone are scarce, due to the extreme conditions of the region. Here, we provide new in situ data from two drifting Surface Wave Instrument Float with Tracking (SWIFT) buoys deployed in the Weddell Sea in the austral winter and spring of 2019. The buoy location ranges from open water to more than 200 km into the sea ice. We estimate the attenuation of swell with wave periods 8–18 s, and find an attenuation coefficientα = 4 · 10⁻⁶to 7 · 10⁻⁵ m⁻¹in spring, and approximately five‐fold larger in winter. The attenuation coefficients show a power law frequency dependence, with power coefficient close to literature. The in situ data also shows a change in wave direction, where wave direction tends to be more perpendicular to the ice edge in sea ice compared to open water. A possible explanation for this might be a change in the dispersion relation caused by sea ice. These observations can help shed further light on the influence of sea ice on waves propagating into marginal ice zones, aiding development of coupled wave‐sea ice models. 

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2. Accelerated sea ice loss in the Wandel Sea points to a change in the Arctic’s Last Ice Area

   https://doi.org/10.1038/s43247-021-00197-5  

   Schweiger, Axel_J; Steele, Michael; Zhang, Jinlun; Moore, G_W_K; Laidre, Kristin_L (July 2021, Communications Earth & Environment)

   Abstract The Arctic Ocean’s Wandel Sea is the easternmost sector of the Last Ice Area, where thick, old sea ice is expected to endure longer than elsewhere. Nevertheless, in August 2020 the area experienced record-low sea ice concentration. Here we use satellite data and sea ice model experiments to determine what caused this record sea ice minimum. In our simulations there was a multi-year sea-ice thinning trend due to climate change. Natural climate variability expressed as wind-forced ice advection and subsequent melt added to this trend. In spring 2020, the Wandel Sea had a mixture of both thin and—unusual for recent years—thick ice, but this thick ice was not sufficiently widespread to prevent the summer sea ice concentration minimum. With continued thinning, more frequent low summer sea ice events are expected. We suggest that the Last Ice Area, an important refuge for ice-dependent species, is less resilient to warming than previously thought. 

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3. Snow in the changing sea-ice systems

   https://doi.org/10.1038/s41558-018-0286-7  

   Webster, Melinda; Gerland, Sebastian; Holland, Marika; Hunke, Elizabeth; Kwok, Ron; Lecomte, Olivier; Massom, Robert; Perovich, Don; Sturm, Matthew (November 2018, Nature Climate Change)
4. Platelet Ice Under Arctic Pack Ice in Winter

   https://doi.org/10.1029/2020GL088898  

   Katlein, Christian; Mohrholz, Volker; Sheikin, Igor; Itkin, Polona; Divine, Dmitry V.; Stroeve, Julienne; Jutila, Arttu; Krampe, Daniela; Shimanchuk, Egor; Raphael, Ian; et al (August 2020, Geophysical Research Letters)

   Abstract The formation of platelet ice is well known to occur under Antarctic sea ice, where subice platelet layers form from supercooled ice shelf water. In the Arctic, however, platelet ice formation has not been extensively observed, and its formation and morphology currently remain enigmatic. Here, we present the first comprehensive, long‐term in situ observations of a decimeter thick subice platelet layer under free‐drifting pack ice of the Central Arctic in winter. Observations carried out with a remotely operated underwater vehicle (ROV) during the midwinter leg of the MOSAiC drift expedition provide clear evidence of the growth of platelet ice layers from supercooled water present in the ocean mixed layer. This platelet formation takes place under all ice types present during the surveys. Oceanographic data from autonomous observing platforms lead us to the conclusion that platelet ice formation is a widespread but yet overlooked feature of Arctic winter sea ice growth. 

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5. Holocene accumulation and ice flow near the West Antarctic Ice Sheet Divide ice core site

   https://doi.org/10.1002/2015JF003668  

   Koutnik, Michelle R.; Fudge, T. J.; Conway, Howard; Waddington, Edwin D.; Neumann, Thomas A.; Cuffey, Kurt M.; Buizert, Christo; Taylor, Kendrick C. (May 2016, Journal of Geophysical Research: Earth Surface)