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This dataset includes the concentrations of dissolved inorganic macronutrients (phosphate, nitrate plus nitrite (N+N), silicic acid, and nitrite), chlorophyll a and phaeophytin, dissolved trace metals (iron, manganese, nickel, zinc, copper), and labile dissolved nickel, as well as pH and total alkalinity measurements, from discrete depth profile samples collected on the FeOA cruise SKQ202209S on R/V Sikuliaq in the Northeast Pacific from June to July 2022. This project investigates the effects of ocean acidification on the associations between iron and organic ligands in seawater and on iron bioavailability to marine phytoplankton communities. The project used a combination of shipboard incubation experiments and depth profiles to characterize iron speciation and cycling across coastal upwelling, oligotrophic open ocean, and iron-limited subarctic oceanographic regimes in the NE Pacific. Surface seawater was incubated at pH of 8.1, 7.6, and 7.1 with natural iron and with dissolved iron amendments in order to investigate interactions between pH and iron bioavailability across the different regimes. Understanding how pH influences iron and its relationship with ligands provides important information for assessing the impacts of ocean acidification on primary production and biogeochemical processes. 

This perspective piece on aerosol deposition to marine ecosystems and the related impacts on biogeochemical cycles forms part of a larger Surface Ocean Lower Atmosphere Study status-of-the-science special edition. A large body of recent reviews has comprehensively covered different aspects of this topic. Here, we aim to take a fresh approach by reviewing recent research to identify potential foundations for future study. We have purposefully chosen to discuss aerosol nutrient and pollutant fluxes both in terms of the journey that different aerosol particles take and that of the surrounding scientific field exploring them. To do so, we explore some of the major tools, knowledge, and partnerships we believe are required to aid advancing this highly interdisciplinary field of research. We recognize that significant gaps persist in our understanding of how far aerosol deposition modulates marine biogeochemical cycles and thus climate. This uncertainty increases as socioeconomic pressures, climate change, and technological advancements continue to change how we live and interact with the marine environment. Despite this, recent advances in modeling techniques, satellite remote sensing, and field observations have provided valuable insights into the spatial and temporal variability of aerosol deposition across the world’s ocean. With the UN Ocean Decade and sustainable development goals in sight, it becomes essential that the community prioritizes the use of a wide variety of tools, knowledge, and partnerships to advance understanding. It is through a collaborative and sustained effort that we hope the community can address the gaps in our understanding of the complex interactions between aerosol particles, marine ecosystems, and biogeochemical cycles.