Substantial loss of isoprene in the surface ocean due to chemical and biological consumption

• Published in: Communications Earth & Environment
• Main Authors: Simó, Rafel, Cortes, Pau, Rodríguez-Ros, P., Masdeu Navarro, Marta
• Other Authors: Ministerio de Economía y Competitividad (España), Agencia Estatal de Investigación (España), La Caixa, European Commission
• Format: Article in Journal/Newspaper
• Language: English
• Published: Nature Publishing Group 2022
• Subjects: Antarctic; Pacific; Antarc*
• Online Access: http://hdl.handle.net/10261/260313; https://doi.org/10.1038/s43247-022-00352-6; https://doi.org/10.13039/501100011033; https://doi.org/10.13039/501100000780; https://doi.org/10.13039/501100003329

8 pages, 4 figures, 1 table, supplementary information https://doi.org/10.1038/s43247-022-00352-6.-- Data availability: All data needed to evaluate the conclusions are available in https://doi.org/10.5281/zenodo.5794234 Isoprene contributes to the formation of ozone and secondary organic aerosol in the atmosphere, and thus influences cloud albedo and climate. Isoprene is ubiquitous in the surface open ocean where it is produced by phytoplankton, however emissions from the global ocean are poorly constrained, in part due to a lack of knowledge of oceanic sink or degradation terms. Here, we present analyses of ship-based seawater incubation experiments with samples from the Mediterranean, Atlantic, tropical Pacific and circum-Antarctic and Subantarctic oceans to determine chemical and biological isoprene consumption in the surface ocean. We find the total isoprene loss to be comprised of a constant chemical loss rate of 0.05 ± 0.01 d−1 and a biological consumption rate that varied between 0 and 0.59 d−1 (median 0.03 d−1) and was correlated with chlorophyll-a concentration. We suggest that isoprene consumption rates in the surface ocean are of similar magnitude or greater than ventilation rates to the atmosphere, especially in chlorophyll-a rich waters This research was supported by the Spanish national funding plan for science through projects PEGASO (CTM2012-37615) and BIOGAPS (CTM2016-81008-R) to RS, and through the 'Severo Ochoa Centre of Excellence' accreditation (CEX2019-000928-S) to the ICM-CSIC. PC-G and MM-N were supported by FPI Ph.D. fellowships from the Spanish national funding plan for science, while PR-R was supported by a 'La Caixa' Foundation Ph.D. fellowship. RS is a holder of a European Research Council Advanced Grant (ERC-2018-ADG-834162) under the EU’s Horizon H2020 research and innovation programme Peer reviewed