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. 2020 Apr 6;11(1):1705.
doi: 10.1038/s41467-020-15485-5.

Faster Atlantic currents drive poleward expansion of temperate phytoplankton in the Arctic Ocean

L Oziel  1   2   3 , A Baudena  4   5 , M Ardyna  5   6 , P Massicotte  7 , A Randelhoff  7 , J-B Sallée  4 , R B Ingvaldsen  8 , E Devred  9 , M Babin  7
Affiliations

Faster Atlantic currents drive poleward expansion of temperate phytoplankton in the Arctic Ocean

L Oziel et al. Nat Commun. .

Abstract

The Arctic marine biome, shrinking with increasing temperature and receding sea-ice cover, is tightly connected to lower latitudes through the North Atlantic. By flowing northward through the European Arctic Corridor (the main Arctic gateway where 80% of in- and outflow takes place), the North Atlantic Waters transport most of the ocean heat, but also nutrients and planktonic organisms toward the Arctic Ocean. Using satellite-derived altimetry observations, we reveal an increase, up to two-fold, in North Atlantic current surface velocities over the last 24 years. More importantly, we show evidence that the North Atlantic current and its variability shape the spatial distribution of the coccolithophore Emiliania huxleyi (Ehux), a tracer for temperate ecosystems. We further demonstrate that bio-advection, rather than water temperature as previously assumed, is a major mechanism responsible for the recent poleward intrusions of southern species like Ehux. Our findings confirm the biological and physical "Atlantification" of the Arctic Ocean with potential alterations of the Arctic marine food web and biogeochemical cycles.

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Conflict of interest statement

The authors declare no competing interests.

Figures

Fig. 1
Fig. 1. The European Arctic Corridor (EAC).
Bathymetry and surface circulation. The Atlantic currents are in red, the Arctic or Polar Waters are in blue and the Coastal Waters are in green. The southern Barents Sea Polar Front is illustrated in black dashed line and separates the Atlantic Waters from the colder and fresher waters from the North.
Fig. 2
Fig. 2. EOF analysis of the MSLA in the European Arctic Corridor.
The sum of the first two modes (a) account for more than 80% of the total variability. The associated time-series (b) experiences a positive linear trend. The blue/red dots correspond to the latitude of the leading-edge of the Ehux blooms in the eastern Barents Sea for longitudes > 40°E (right red y-axis), which strongly correlates with the yearly averaged EOF-1+EOF-2 time-series (r = 0.77, p = 0.0002, two-sided t-test).
Fig. 3
Fig. 3. Increasing current velocities in the European Arctic Corridor.
Surface absolute geostrophic velocities during the extremums of the time-series which are, respectively, reached in December 1993 (a, minimum) and 2015 (b, maximum) with the corresponding absolute linear trend of the entire time-series (all months) over the 1993–2016 period (c). Areas covered by sea ice (sea-ice concentration > 15%) or with insufficient data coverage for the trend (<50%) are in dark gray.
Fig. 4
Fig. 4. Poleward expansion of Emiliania Huxleyi (EHux) in the European Arctic Corridor.
Comparison between 1998 (a) and 2015 (b). The initialization (inoculum) of virtual particles in March are illustrated by brown dots. During 6 months, particles drift with the Norwegian Atlantic Current (red arrows) as the ocean seasonally warms as illustrated by the northward expansion of the 4 °C isotherm. In August, the particles end up in positions indicated by the red dots. In the background, remotely sensed PIC indicating coccolithophore biomass in summer (July–August–September) is shown in blue colors. Areas with no data are in dark gray.
Fig. 5
Fig. 5. Shifting position of the leading-edge Ehux bloom distribution.
Shifting position from ocean-color PIC (a), and the 3 Lagrangian experiments (b–d) for the last 19-years (1998–2016). The comparison between the 1st Lagrangian experiment (EXP1, b) with the 2nd (EXP2, c) and the 3rd (EXP3, d) aims at estimating the relative contribution of currents (EXP2, constant temperature) vs. temperature (EXP3, constant currents) on the total Ehux poleward expansion (EXP1, varying temperature and currents). The right panel is a schematic illustration of the poleward expansion of the Ehux with the winter 4 °C isotherm (lowest temperature for a ‘regular’ Ehux growth) in blue and the summer bloom position (northern boundary) in red. The two extreme years 1998 (dashed) and 2015 (solid) are represented. Arrows indicate the contribution from temperature and/or currents keeping the same color code.
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References

    1. Wassmann P, Slagstad D, Ellingsen I. Primary production and climatic variability in the European sector of the Arctic Ocean prior to 2007: preliminary results. Polar Biol. 2010;33:1641–1650. doi: 10.1007/s00300-010-0839-3. - DOI
    1. Huang J, et al. Recently amplified arctic warming has contributed to a continual global warming trend. Nat. Clim. Chang. 2017;7:875–879. doi: 10.1038/s41558-017-0009-5. - DOI
    1. Stroeve J, Notz D. Changing state of Arctic sea ice across all seasons. Environ. Res. Lett. 2018;13:103001. doi: 10.1088/1748-9326/aade56. - DOI
    1. Oziel L, Sirven J, Gascard JC. The Barents Sea frontal zones and water masses variability (1980–2011) Ocean Sci. 2016;12:169–184. doi: 10.5194/os-12-169-2016. - DOI
    1. Årthun M, Eldevik T, Smedsrud LH, Skagseth Øystein, Ingvaldsen RB. Quantifying the influence of atlantic heat on barents sea ice variability and retreat. J. Clim. 2012;25:4736–4743. doi: 10.1175/JCLI-D-11-00466.1. - DOI

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