Remote Sensing Retrieval of Isoprene Concentrations in the Southern Ocean

• Published in: Geophysical Research Letters
• Main Authors: Rodríguez-Ros, P., Galí, Martí, Cortes, Pau, Robinson, Charlotte Mary, Antoine, D., Wohl, Charel, Yang, Ming-Xi, Simó, Rafel
• Other Authors: Ministerio de Economía y Competitividad (España), Australian Research Council, Swiss Polar Institute, Ferring Pharmaceuticals, La Caixa, Agencia Estatal de Investigación (España)
• Format: Article in Journal/Newspaper
• Language: English
• Published: American Geophysical Union 2020
• Subjects: Antarctic; Southern Ocean; The Antarctic; Antarc*; Swiss Polar Institute
• Online Access: http://hdl.handle.net/10261/216315; https://doi.org/10.1029/2020GL087888; https://doi.org/10.13039/501100003329; https://doi.org/10.13039/501100000923; https://doi.org/10.13039/501100004914; https://doi.org/10.13039/501100011033

10 pages, 4 figures, supporting information https://doi.org/10.1029/2020GL087888.-- Data are available at the Zenodo repository (https://doi.org/10.5281/zenodo.3822547, DOI:10.5281/zenodo.3822547) Isoprene produced by marine phytoplankton acts as a precursor of secondary organic aerosol and thereby affects cloud formation and brightness over the remote oceans. Yet the marine isoprene emission is poorly constrained, with discrepancies among estimates that reach 2 orders of magnitude. Here we present ISOREMS, the first satellite‐only based algorithm for the retrieval of isoprene concentration in the Southern Ocean. Sea surface concentrations from six cruises were matched with remotely sensed variables from MODIS Aqua, and isoprene was best predicted by multiple linear regression with chlorophyll a and sea surface temperature. Climatological (2002–2018) isoprene distributions computed with ISOREMS revealed high concentrations in coastal and near‐island waters, and within the 40–50°S latitudinal band. Isoprene seasonality paralleled phytoplankton productivity, with annual maxima in summer. The annual Southern Ocean emission of isoprene was estimated at 63 Gg C yr−1. The algorithm can provide spatially and temporally realistic inputs to atmospheric and climate models This research was funded by the Spanish Ministry of Economy and Competitiveness through projects PEGASO (CTM2012‐37615) and BIOGAPS (CTM2016‐81008‐R) to R. S., and partially by the Australian Government through the Australian Research Council's Discovery Projects funding scheme (project DP160103387). The Antarctic Circumnavigation Expedition was made possible by funding from the Swiss Polar Institute and Ferring Pharmaceuticals. P. R. R. was supported by a “la Caixa” Foundation PhD Fellowship (2015-2019) With the funding support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S), of the Spanish Research Agency (AEI) Peer reviewed