375 / 2024-09-15 17:05:53

Impact of atmospheric deposition on marine ecosystem in the North Pacific Ocean

atmospheric deposition,primary production,dust,physical-biological model

Session 25 - IGAC-SOLAS: Chemistry and physics at surface ocean and lower atmosphere

North Pacific Ocean is characterized as both high nutrient and low chlorophyll (HNLC) in the subarctic region and low nutrient and low chlorophyll (LNLC) in the subtropic region. The growth of phytoplankton is strictly restricted by the supply of major and minor nutrients. For the open ocean, atmospheric deposition (atmospheric pollutants produced by human activities as well as dust) is an important source of nitrogen and iron, which can impact biological activities in the upper layer of the ocean. The daily-averaged atmospheric deposition is quantified in the North Pacific Ocean, as well as its spatial and temporal variability. High flux of atmospheric deposition flux happens during spring and peaks in May, and low values occur in winter. The spatial distribution of atmospheric deposition shows a prominent increasing from the northwest towards the northeast. The response of Particulate Organic Carbon (POC) and chlorophyll at station K2 (47°N, 160°E) to strong dust events are investigated from observation and numerical model. The supply of nutrient from atmospheric deposition plays an important role in regulating the growth of phytoplankton and biological pump, implying a potential method for mitigating climate change through geoengineering approach.