LAUSR

The 90Sr activities of seawater were investigated in the high-latitude region of the Arctic Ocean from August-September 2017. The 90Sr activities in seawater in the Chukchi Sea, central Arctic Ocean and East Greenland Sea were 0.31-2.42, 0.12-1.86 and 0.13-1.20 Bq m-3, respectively. The average 90Sr activity (0.92 Bq m-3) below 500 m in the central Arctic Ocean was higher than those in previous reports. Our study provided high-resolution baseline 90Sr activity data for the whole water column in the high-latitude region of the Arctic Ocean (~85°N). The inventory of 90Sr in the central Arctic Ocean was higher than those in the Chukchi Sea and East Greenland Sea. The results of our study indicated that 90Sr could be transported to the deep seawater and remain in the Arctic Ocean for a long time.