An innovative tool for the assessment of coccolithophore blooms' impact on marine carbon sinks in subarctic and arctic seas

Theme 3. Meteorological Cooperation
Session Name 3.1 Opportunities and challenges of remote sensing techniques to meet current and future needs for monitoring the Arctic
Location Room 15
Presentation Type Poster
Presenter Dmitry Pozdnaykov
Author(s) Dmitry Pozdnaykov (Nansen International Environmental and Remote Sensing Centre, Russian Federation), Dmitry Kondrik (Nansen International Environmental and Remote Sensing Centre, Russian Federation)
Abstract text

Coccolithophore E. huxleyi cause less uptake of atmospheric CO2 by the ocean. A global assessment of this phenomenon has so far not been quantified. Applying our innovative biogeochemical algorithm based on multivariate optimization technique, and using Ocean Colour Satellite time series data for a 19-year period (1998-2016)  we quantified the CO2 partial pressure increase (ΔpCO2) within E. huxleyi blooms in the North, Norwegian, Greenland, Barents, and Bering Seas. E. huxleyi outbursts in the North Atlantic and Arctic Seas. They  proved to occur annually, but their extent vary interannually.  In the Bering Sea, during 1998-2001 there was a splash in blooming activity followed by a drastic drop. The bloom duration in the Bering Sea in 1997/98-2001 reached 10 months, in the North Atlantic seas it was ~ 1 month. The maximum inorganic carbon content in E. huxleyi blooms in all seas varied over the 19 years between ~ 15 and 70 Kt. When normalized to pCO2 in the absence of bloom, the mean and maximum ΔpCO2 values within the bloom areas varied in percent between 21.0 – 43.3 and 31.6 - 62.5, respectively.  As huge outbursts of E. huxleyi also occur in the southern hemisphere, such blooms unfold in the world oceans across the entire year. Our data can serve as a baseline for assessing the importance of the phenomenon for climatology, marine chemistry and ecology on a global scale. We express our gratitude for the financial support of this study provided by the Russian Science Foundation (RSF) under the project 17-17-01117.