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Producing very extensive blooms in the world’s oceans in both hemispheres, a coccolithophore E. huxleyi affects both
marine ecology and carbon fluxes at the atmosphere-ocean interface. In turn, it is subject to impacts of multiple co-acting
environmental forcings responsible for spatio-temporal dynamics in E. huxleyi blooms.
To reveal the individual importance of each forcing factor (FF) that is known to significantly control the extent and
intensity of E. huxleyi blooms, the 1998-2016 spaceborne time series of sea surface temperature and salinity, incident
photosynthetically active radiation, and the Ekman depth relevant to the North, Norwegian, Greenland, Labrador,
Barents and Bering seas were employed.
The descriptive statistical approach showed that E. huxleyi phytoplankton blooms were capable of arising and developing
within wide but expressly sea-specific FFs ranges. Sea-specific FFs ranges, within which the blooms are particularly
extensive were identified.
The Random Forest Classifier (RFC) allowed to reliably rank the FFs in terms of their role in E. huxleyi bloom spatiotemporal
dynamics in each target sea. High prediction ability of RFC modelling (>70%) confirms the adequacy of the
developed FFs prioritization models.
Although the parameters of the carbon chemistry system per se were beyond consideration, however, over the twenty
years of observations, the prioritized FFs have not failed to explain the registered patterns of the spatial extent of and
particulate inorganic carbon content in E. huxleyi blooms. Also, several verifications (pastcasts) showed a high degree of
their consistency with the observations. Collectively, these results tell in favor of sufficiency of the FFs employed.
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