Reduced marine phytoplankton sulphur emissions in the Southern Ocean during the past seven glacials.

ABSTRACT: Marine biogenic sulphur affects Earth's radiation budget and may be an indicator of primary productivity in the Southern Ocean, which is closely related to atmospheric CO₂ variability through the biological pump. Previous ice-core studies in Antarctica show little climate dependence of marine biogenic sulphur emissions and hence primary productivity, contradictory to marine sediment records. Here we present new 720,000-year ice core records from Dome Fuji in East Antarctica and show that a large portion of non-sea-salt sulphate, which was traditionally used as a proxy for marine biogenic sulphate, likely originates from terrestrial dust during glacials. By correcting for this, we make a revised calculation of biogenic sulphate and find that its flux is reduced in glacial periods

SUBMITTER: Goto-Azuma K 

PROVIDER: S-EPMC6642193 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature