BGC-09 Biogeochemistry in Subtropical Oceans
Estimation of atmospheric iron inputs to the NPSG based on field sampling
Wenkai Guan* , a. Frontiers Science Center for Deep Ocean Multispheres and Earth System, and Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao 266100, China.
Qian Liu, a. Frontiers Science Center for Deep Ocean Multispheres and Earth System, and Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao 266100, China.
Qian He, a. Frontiers Science Center for Deep Ocean Multispheres and Earth System, and Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao 266100, China.
Ruifeng Zhang, b. School of Oceanography, Department of Marine Chemistry, Shanghai Jiao Tong University, Shanghai, China
Jing Zhang, a. Frontiers Science Center for Deep Ocean Multispheres and Earth System, and Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao 266100, China. c. Earth and Environmental System, Graduate School of Science and Engineering, University of Toyama, Japan.

 Iron is identified as an important limiting nutrient in the western subtropical North Pacific. Atmospheric deposition may contribute significant amounts of the nutrients Fe to this region. To quantify (seasonal and spatial basis) the atmospheric input of dissolved Fe (dFe), sampling was conducted during 3 GEOTRACES cruises, and a dataset of measured concentrations of dFe in aerosol and rainfall was acquired. The results showed that the annual flux of atmospheric dFe input was about 0.12-0.82 mg m-2 yr-1. The dFe concentrations in rainfall and aerosol were significantly higher in spring than that in summer and winter, suggesting the impact of Asian dust. Moreover, wet deposition plays an important role in the south reigon while dry deposition contributes more in the north. This may affect the nutrient structure of surface ecosystem.