Importance of lateral transport processes to Pb-210 budget in the eastern Chukchi Sea during summer 2003

• Main Authors: Chen, Min, Ma, Qiang, Guo, Laodong, Qiu, Yusheng, Li, Yanping, Yang, Weifeng, 陈敏, 杨伟锋
• Format: Article in Journal/Newspaper
• Language: English
• Published: DEEP-SEA RES PT II 2012
• Subjects: PARTICULATE ORGANIC-CARBON; WESTERN ARCTIC-OCEAN; MIDDLE ATLANTIC BIGHT; CONTINENTAL-MARGIN; CANADA BASIN; BERING-SEA; BIOLOGICAL PRODUCTIVITY; SURFACE WATERS; EXPORT FLUXES; POC EXPORT; Arctic; Arctic Ocean; Bering Sea; Chukchi Sea; Canada; Pacific; canada basin; Chukchi; IPY; Sea ice
• Online Access: http://dspace.xmu.edu.cn/handle/2288/87847

Chinese IPY Research Program; National Natural Science Foundation of China [41125020]; Fujian Natural Science Foundation [2009J06026]; State Oceanic Administration of China [201105022-4]; Ministry of Education of China Activity concentrations of dissolved and particulate Pb-210 and Ra-226 in the water column were measured in the eastern Chukchi Sea during summer 2003. Th-234/U-238 disequilibria were used to estimate the scavenging fluxes of Pb-210 from the water column to the underlying sediments. Our results showed that concentrations of Pb-210 and its distributions were mainly influenced by mixing processes of water masses and sediment resuspension. The residence times of Pb-210 in the eastern Chukchi Sea ranged from 5 to 103 d. Short residence times were mostly observed at the shelf stations, indicating a more effective particle scavenging in the shelf region. A mass balance model was constructed to evaluate the contribution of lateral transport to Pb-210 budget in the water column. The lateral transport fluxes of Pb-210 ranged from 17 to 177 Bq/m(2)/a, comprising up to 63-94% of the total supply of Pb-210 in the eastern Chukchi Sea. We hypothesize that the accumulative removal of Pb-210 in the Pacific inflow waters during their transport across the Chukchi Sea and the import of Pb-210 from sea ice rafted sediments are the two major lateral transport pathways for the import of Pb-210 to the eastern Chukchi Sea. Our results highlight the importance of lateral transport processes to the geographical distribution of particle-reactive elements and their biogeochemical cycles in the Arctic Ocean. (C) 2012 Elsevier Ltd. All rights reserved.