Researchers at the Nansen Center developed a new method to ultimately make navigation in the Arctic Ocean safer!
Ship traffic in the Arctic can be risky business: Sea ice can slow down ships, and even damage them if it is too thick. To avoid that, routes are planned to go through zones with either just open water where that is possible, or through zones with thin ice. So-called leads – cracks that open in the sea-ice cover and freeze over again after a while – can also be used as routes. They form because sea ice is continuously in motion due to winds and ocean currents. The ice can therefore both be “pulled apart”, leading to leads, and “pushed together”, forming ridges. Ridges are accumulations of ice: They can be significantly thicker than the surrounding sea ice, making them dangerous for ship traffic.
To know about sea-ice deformation and the positions of leads and ridges in the Arctic is crucial for safe navigation. Instruments onboard satellites hundreds of kilometers above the sea-ice cover can produce observations that can help identifying their positions. The ice-charting community uses these observations to produce maps of the Arctic that show where it is relatively safe to sail and where it is not safe. Ice chart production is labour-intensive, and the community can benefit from more accurate data than only satellite observations – their spatial resolution is limited. One way to achieve that is to forecast with sea-ice models.
This is where several Nansen Center researchers come in: Under the lead of Anton Korosov, they developed a method to use and include satellite observation-derived information on sea-ice deformation (including the position of leads and ridges) into sea-ice models. Sea-ice models can be used to make forecasts several days in advance. Korosov and his colleagues show that their method improves the accuracy of the forecasted positions of leads and ridges for three to four days! Knowing where waters are safe and not safe several days in advance makes adjusting routes safer.
Korosov and his colleagues advocate for the use of sea-ice deformation data in sea-ice models, to improve short-term forecasting. Their findings will hopefully inspire the ice charting community and navigators to also use sea-ice model data for route planning.
