195 



Hearing on Radioactive and Asker Aarkrog, D.Sc. 



other Environmental Threats Rise National Laboratory 



to the Arctic resulting from DK-40(X) Roskilde 

 past Soviet activities. Denmark 



Alaska-Fairbanks 

 Aug. 15, 1992 



ENVIRONMENTAL RADIOACTIVITY IN 

 THE ARCTIC 



Definition of the Arctic 



In the present context the Arctic regions comprises all areas north of the arctic circle. 

 The major part of the area is the Arctic Ocean and the inland ice of Greenland, but it 

 also includes the northern parts of the European, Asian and American continents. 



Characteristics of the Arctic reyions 



The low temperature and large amplitude photocycle (dark winters and nightless 

 summers) are the primary factors which influence the arctic ecosystems. Although the 

 atmospheric deposition in Arctic regions tends to be low the impact of pollution on the 

 ecosystems may be significant. This is due to the often long residencetimes of pollutants 

 and to the high sensitivity of arrtic ecosystems because the organisms in these systems 

 already are under severe stress due to the unfavourable living conditions. The foodchains 

 are usually formed by a few species which means they have large natural fluctuations. 

 They are thus more weakly balanced than we know it from temperate and tropical 

 ecosystems. 



Sources and inventories of radioactive contamination 



The concern for the Arctic in coimection with radioactive contamination came up in the 

 early sixties when multimegatons nuclear weapons were tested at the USSR Novaya 



