Large diatom bloom off the Antarctic Peninsula during cool conditions associated with the 2015/2016 El Niño

Abstract Diatoms play crucial functions in trophic structure and biogeochemical cycles. Due to poleward warming, there has been a substantial decrease in diatom biomass, especially in Antarctic regions that experience strong physical changes. Here we analyze the phytoplankton contents of water sampl...

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Bibliographic Details
Published in:Communications Earth & Environment
Main Authors: Costa, Raul Rodrigo, Mendes, Carlos Rafael Borges, Ferreira, Afonso, Tavano, Virginia Maria, Dotto, Tiago Segabinazzi, Secchi, Eduardo Resende
Other Authors: EC | Horizon 2020 Framework Programme, Ministry of Science, Technology and Innovation | Conselho Nacional de Desenvolvimento Científico e Tecnológico
Format: Article in Journal/Newspaper
Language:English
Published: Springer Science and Business Media LLC 2021
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Online Access:http://dx.doi.org/10.1038/s43247-021-00322-4
https://www.nature.com/articles/s43247-021-00322-4.pdf
https://www.nature.com/articles/s43247-021-00322-4
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Summary:Abstract Diatoms play crucial functions in trophic structure and biogeochemical cycles. Due to poleward warming, there has been a substantial decrease in diatom biomass, especially in Antarctic regions that experience strong physical changes. Here we analyze the phytoplankton contents of water samples collected in the spring/summer of 2015/2016 off the North Antarctic Peninsula during the extreme El Niño event and compare them with corresponding satellite chlorophyll- a data. The results suggest a close link between large diatom blooms, upper ocean physical structures and sea ice cover, as a consequence of the El Niño effects. We observed massive concentrations (up to 40 mg m –3 of in situ chlorophyll- a ) of diatoms coupled with substantially colder atmospheric and oceanic temperatures and high mean salinity values associated with a lower input of meltwater. We hypothesize that increased meltwater concentration due to continued atmospheric and oceanic warming trends will lead to diatom blooms becoming more episodic and spatially/temporally restricted.