title: Carbon dynamics within cyclonic eddies: insights from a biomarker study.
abstract: It is generally assumed that episodic nutrient pulses by cyclonic eddies into surface waters support a significant fraction of the primary production in subtropical low-nutrient environments in the northern hemisphere. However, contradictory results related to the influence of eddies on particulate organic carbon (POC) export have been reported. As a step toward understanding the complex mechanisms that control export of material within eddies, we present here results from a sediment trap mooring deployed within the path of cyclonic eddies generated near the Canary Islands over a 1.5-year period. We find that, during summer and autumn (when surface stratification is stronger, eddies are more intense, and a relative enrichment in CaCO3 forming organisms occurs), POC export to the deep ocean was 2-4 times higher than observed for the rest of the year. On the contrary, during winter and spring (when mixing is strongest and the seasonal phytoplankton bloom occurs), no significant enhancement of POC export associated with eddies was observed. Our biomarker results suggest that a large fraction of the material exported from surface waters during the late-winter bloom is either recycled in the mesopelagic zone or bypassed by migrant zooplankton to the deep scattering layer, where it would disaggregate to smaller particles or be excreted as dissolved organic carbon. Cyclonic eddies, however, would enhance carbon export below 1000 m depth during the summer stratification period, when eddies are more intense and frequent, highlighting the important role of eddies and their different biological communities on the regional carbon cycle.
authors.affiliation: Instituto de Oceanografía y Cambio Global (IOCAG), Universidad de Las Palmas de Gran Canaria, Las Palmas de Gran Canaria, Spain ; Spanish Bank of Algae (BEA), Telde, Spain.
authors.forename: Iván J
authors.initials: IJ
authors.lastname: Alonso-González
authors.affiliation: Instituto de Oceanografía y Cambio Global (IOCAG), Universidad de Las Palmas de Gran Canaria, Las Palmas de Gran Canaria, Spain.
authors.forename: Javier
authors.initials: J
authors.lastname: Arístegui
authors.affiliation: School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, New York, United States of America.
authors.forename: Cindy
authors.initials: C
authors.lastname: Lee
authors.affiliation: GRC Geociències Marines, Facultat de Geologia, Universitat de Barcelona, Barcelona, Spain.
authors.forename: Anna
authors.initials: A
authors.lastname: Sanchez-Vidal
authors.affiliation: GRC Geociències Marines, Facultat de Geologia, Universitat de Barcelona, Barcelona, Spain.
authors.forename: Antoni
authors.initials: A
authors.lastname: Calafat
authors.affiliation: UNEP Shelf Programme Facility, UNEP/GRID-Arendal, Arendal, Norway.
authors.forename: Joan
authors.initials: J
authors.lastname: Fabrés
authors.affiliation: Instituto de Oceanografía y Cambio Global (IOCAG), Universidad de Las Palmas de Gran Canaria, Las Palmas de Gran Canaria, Spain.
authors.forename: Pablo
authors.initials: P
authors.lastname: Sangrá
authors.affiliation: Grup d'Oceanografia Fisica, Institut de Ciències del Mar, CMIMA-CSIC, Barcelona, Spain ; Mediterranean Institute for Advanced Studies (IMEDEA), Esporles, Spain.
authors.forename: Evan
authors.initials: E
authors.lastname: Mason
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000032:analysis / Q000737:chemistry; D002244:Carbon / Q000032:analysis* / Q000737:chemistry; D055867:Cyclonic Storms; D012621:Seasons; D012623:Seawater / Q000737:chemistry*; D013030:Spain; D014872:Water Movements; D015048:Zooplankton / Q000502:physiology
chemical_list: D015415:Biomarkers; D002244:Carbon