Radionuclide Dispersion
Nuclear deposits in coastal glaciers in the Arctic may be released with increased melting, threatening human and environmental health.
Nuclear testing between 1957 and 1963 deposited long-lived radionuclides on glaciers, particularly around the Novaya Zemlya archipelago in the Kara sea. Melting glacier ice could result in the release of these long-lived radionuclides into the sea, threatening human and environmental health. In addition, there may be radioactive leakage from other sources such as sunken radioactive waste, reactors, and submarines.
Storylines
The final storyline was selected taking into account important factors of climate variability in the Arctic such as warming of the Barents-Kara seas, which can have an impact on radionuclide dispersion in regional or global scales. In this section, you will find how one of our Arctic storylines impacts radionuclide dispersion from contaminated coastal glaciers on the Novaya Zemlya archipelago and sunken solid radioactive wastes, reactors, and submarines in the Kara Sea, and what this means for the environment and global human health.
To assess these impacts, a 3D Lagrangian radionuclide particle tracking model is used to simulate radionuclide transport in the Arctic Ocean based on high resolution simulations of the ocean with NEMO. A novel probabilistic approach for transforming particles’ states, including radioactive decay, adsorption-desorption in bed and suspended sediments, erosion, and deposition is developed. We consider 4 scenarios based on historical and projected storm events. In these scenarios, potential contamination of water and sediments due to releases of Caesium-137 (137Cs) in 4 locations of sunken submarines K-159 and “Komsomolets”, dumped K-27, and Novaya Zemlya coast are considered.
The results show that the transport pathways of 137Cs in the Arctic Ocean was highly influenced by the depth of the radioactive outflow. Other factors influencing the pathway included the source locations and changes in ocean circulation. Besides, the portion of 137Cs ending up in the bottom sediments is less than 1% for the submarine in deep water while it was more than 85% for the shallow water submarine fjord of Abrosimov in the Kara Sea. Under future climate projections, the transport pathways change little but the amount of radioactivity ending up in the bottom sediment changes by more than 50%.
Currently, no significant radioactive leaks from locations of dumped materials and sunk submarines have been detected in the Arctic Ocean. However, such sources may emerge in the future, particularly as a result of melting coastal glaciers on Novaya Zemlya. Therefore, monitoring of these locations, including bottom sediments, is necessary in the next decades.