High-resolution Sampling Reveals Episodic Dust Outbreaks and Their Impact on the Marine Carbon Sink

Data collected between August 2017 and December 2018 from submarine sediment traps in the eastern tropical North Atlantic with sampling intervals of four days allowed for the identification of thirteen major dust events of two types. High-flux events were identified by a deposition of ≥25 mg m^-2 d^-1 while anomalous grain-size events were characterised by a composition of giant particles >7.3 vol%. The average dust deposition rate increased by 461.3% during high-flux events. While organic matter (OM) was continuously deposited at the sampling site with an average rate of 115.6 mg m^-2 d^-1, the flux increased by 199.5% during high-flux events but decreased by 13.6% during anomalous grain-size events. Our data suggest a possible dust fertilisation or mineral ballasting effect during high-flux events, indicating that dust outbreaks impact the marine carbon sink.

Reference: Matzenbacher, B.A., Brummer, G.-J.A., Prins, M.A. & Stuut, J.-B.W. (2024). High-resolution sampling in the eastern tropical North Atlantic reveals episodic Saharan dust deposition: Implications for the marine carbon sink. Front. Mar. Sci., 11, 1367786. https://doi.org/10.3389/fmars.2024.1367786