Lagrangian modeling of Arctic ocean circulation pathways: impact of advection on spread of pollutants

• Published in: Journal of Geophysical Research: Oceans
• Main Authors: Kelly, S., Popova, E., Aksenov, Y., Marsh, R., Yool, A.
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2018
• Subjects: Arctic; Arctic Ocean; Northern Sea Route; Sea ice
• Online Access: https://eprints.soton.ac.uk/422056/; https://eprints.soton.ac.uk/422056/1/Kelly_et_al_2018_Journal_of_Geophysical_Research_3A_Oceans.pdf

Sea-ice-free summers are projected to become a prominent feature of the Arctic environment in the coming decades. From a shipping perspective, this means larger areas of open water in the summer, thinner and less compact ice all year round, and longer operating seasons. Therefore, the possibility for easier navigation along trans-Arctic shipping routes arises. The Northern Sea Route (NSR) is one trans-Arctic route, and it offers a potential 10 day shortcut between Western Europe and the Far East. More ships transiting the NSR means an increased risk of an accident, and associated oil spill, occurring. Previous research suggests that current infrastructure is insufficient for increased shipping. Therefore, should an oil spill occur, the window for a successful clean-up will be short. In the event of a failed recovery, the long-term fate of the unrecovered pollutants must be considered, at least until the next melt season when it could become accessible again. Here we investigate the role of oceanic advection in determining the long-term fate of Arctic pollutants using a high-resolution ocean model along with Lagrangian particle-tracking to simulate the spread of pollutants. The resulting “advective footprints” of pollutants are proposed as an informative metric for analyzing such experiments. We characterize the circulation along different parts of the NSR, defining three main regions in the Eurasian Arctic, and relate the distinctive circulation pathways of each to the long-term fate of spilled oil. We conclude that a detailed understanding of ocean circulation is critical for determining the long-term fate of Arctic pollutants.