Simulation Scenarios for Potential Radioactive Spreading in the 21 st Century from Rivers and External Sources in the Russian Arctic Coastal Zone.

The overall objective of RADARC’s research programme is to perform simulation scenarios for the 21st century, including global warming scenarios, of potential radioactive spreading from sources in the Russian Arctic coastal zone and its impact
on Barents, Greenland and Norwegian Seas and the Arctic Ocean in order to supportdecision making for: risk prevention, forecasting and preparedness for probable crisis, alert and detection, relief and mitigation and damage assessment. These studies were realised using hydrodynamic modelling of the rivers, estuaries, coastal Kara Sea and the open ocean aquatic systems of the northern Russia and the Arctic and a related comprehensive database that was organised in a Geographical Information System (GIS). Under the RADARC project a new modelling approach was implemented using Generic Model System, where the four types of models were
integrated and merged.
The Generic Model System (GMS) that was created for the first time include the GIS and an interactive hydrodynamic models chain for simulations of radionuclide transport from relevant land-based sources through the river and estuary system to and in the Kara Sea as well as in the Arctic and North Atlantic Oceans. The GMS consist of four adopted and validated hydrodynamic models: a medium resolution (50 km) 3-D numerical ice-ocean model for the Arctic and North Atlantic Ocean; nested with a high resolution (5 km) model for the Kara Sea including a sediment module; nested with the river model system including a one-dimensional model of river dynamics and radionuclide transport and three-dimensional model of Ob ́ and Yenisey estuarine and coastal areas hydrodynamics and radionuclide transport model.
The most probable release scenarios for radionuclides were developed and simulation studies for selected future scenarios of radionuclear contamination was carried-out, using atmospheric forcing scenarios, including global warming, likely consistent with
a CO2 doubling and control runs. Thus a new tool for an assessment of the potential radioactive spreading in the Arctic was created and the assessment of the potential radioactive spreading from rivers and external sources in the Russian Arctic Coastal Zone was developed and assessed