Distribution and Drivers of Marine Isoprene Concentration across the Southern Ocean

• Published in: Atmosphere
• Main Authors: Rodríguez-Ros, P., Cortes, Pau, Robinson, Charlotte Mary, Nunes, Sdena, Hassler, Christel S., Royer, S.-J., Estrada, Marta, Sala, M. Montserrat, Simó, Rafel
• Other Authors: Ministerio de Economía y Competitividad (España), Swiss Polar Institute, Ferring Pharmaceuticals, Council for Scientific and Industrial Research (India), University of Cape Town, Australian Research Council, Fundación "la Caixa", Agencia Estatal de Investigación (España)
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: Multidisciplinary Digital Publishing Institute 2020
• Subjects: Isoprene; Southern Ocean; Drivers; Phytoplankton; Blooms; Lagrangian; Antarctic circumnavigation; Antarctic; Near Islands; Antarc*; Swiss Polar Institute
• Online Access: http://hdl.handle.net/10261/213461; https://doi.org/10.3390/atmos11060556; https://doi.org/10.13039/501100000923; https://doi.org/10.13039/501100003329; https://doi.org/10.13039/501100007112; https://doi.org/10.13039/501100004914; https://doi.org/10.13039/501100011033

Special issue The Interrelationships between Near-Surface Ecological Processes and Air–Sea Exchange of Gases and Particles.-- 19 figures, 5 figures, 2 tables, 2 appendices.-- Data of this work can be found at the Zenodo repository (https://doi.org/10.5281/zenodo.3773972).-- This research is part of POLARCSIC (https://polarcsic.es/) activities soprene is a biogenic trace gas produced by terrestrial vegetation and marine phytoplankton. In the remote oceans, where secondary aerosols are mostly biogenic, marine isoprene emissions affect atmospheric chemistry and influence cloud formation and brightness. Here, we present the first compilation of new and published measurements of isoprene concentrations in the Southern Ocean and explore their distribution patterns. Surface ocean isoprene concentrations in November through April span 1 to 94 pM. A band of higher concentrations is observed around a latitude of ≈40 ∘ S and a surface sea temperature of 15 ∘ C. High isoprene also occurs in high productivity waters near islands and continental coasts. We use concurrent measurements of physical, chemical, and biological variables to explore the main potential drivers of isoprene concentration by means of paired regressions and multivariate analysis. Isoprene is best explained by phytoplankton-related variables like the concentrations of chlorophyll-a, photoprotective pigments and particulate organic matter, photosynthetic efficiency (influenced by iron availability), and the chlorophyll-a shares of most phytoplankton groups, and not by macronutrients or bacterial abundance. A simple statistical model based on chlorophyll-a concentration and a sea surface temperature discontinuity accounts for half of the variance of isoprene concentrations in surface waters of the Southern Ocean This research was supported by the Spanish Ministry of Economy and Competitiveness through project PEGASO (CTM2012–37615) to RS, and by the Swiss Polar Institute and Ferring Pharmaceuticals through project SORPASSO–ACE#8 to RS and project ACE#1 ...