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Abstract Straits are strategically and economically vital due to their role as maritime choke points, controlling access to regions and resources. This is particularly pertinent in the Arctic, where navigability along critical shipping routes relies on access through straits that are frequently ice impacted. With the retreat of Arctic sea ice under anthropogenic climate change, scenarios using CMIP6 projections have the potential to provide valuable insights into future maritime accessibility regimes. However, typical climate model spatial resolutions limit the capacity to represent Arctic straits accurately. This study introduces a novel approach, the sea Ice Concentration Enhancement Generative Adversarial Network (ICE‐GAN), to enhance the spatial resolution of sea ice concentration (SIC) in Vilkitsky Strait, a passage along the Northern Sea Route (NSR). By employing the ICE‐GAN model, the spatial resolution is functionally increased from to . The approach is prototyped using ERA5 Reanalysis training data to predict ice cover for 2021 and 2022. The results indicate that the ICE‐GAN method outperforms, across multiple metrics, standard interpolation techniques such as Nearest Neighbor Interpolation and Bilinear Interpolation, both used in maritime accessibility models, as well as the super‐resolution convolutional neural network, the best practice method for super‐resolution in SIC. Importantly, the approach is robust to the non‐stationarity of the sea ice record. Moreover, by incorporating a physics‐informed approach into the ICE‐GAN, the model is able to further improve the accurate representation of sea ice cover in the studied Strait.
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The interaction of ice and law in Arctic marine accessibility
Sea ice levies an impost on maritime navigability in the Arctic, but ice cover diminution due to anthropogenic climate change is generating expectations for improved accessibility in coming decades. Projections of sea ice cover retreating preferentially from the eastern Arctic suggest key provisions of international law of the sea will require revision. Specifically, protections against marine pollution in ice-covered seas enshrined in Article 234 of the United Nations Convention on the Law of the Sea have been used in recent decades to extend jurisdictional competence over the Northern Sea Route only loosely associated with environmental outcomes. Projections show that plausible open water routes through international waters may be accessible by midcentury under all but the most aggressive of emissions control scenarios. While inter- and intraannual variability places the economic viability of these routes in question for some time, the inevitability of a seasonally ice-free Arctic will be attended by a reduction of regulatory friction and a recalibration of associated legal frameworks.
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- Award ID(s):
- 2022599
- PAR ID:
- 10353184
- Date Published:
- Journal Name:
- Proceedings of the National Academy of Sciences
- Volume:
- 119
- Issue:
- 26
- ISSN:
- 0027-8424
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1073/pnas.2202720119
