Here we investigate properties of ocean eddies in the key Arctic region of the northern Greenland Sea and the Fram Strait using visible and infrared Moderate Resolution Imaging Spectroradiometer (MODIS) Aqua data acquired from April to September in 2007 and 2018–2020. We infer eddy properties using visual identification and automated processing of their signatures in sea surface temperature (SST) and chlorophyll-a (chl-a) maps, and their gradients. Altogether, 450 (721) eddies were identified in SST (chl-a) data. Their radii span from 2 to 40 km (mean value 12 km). Most eddies are elliptical with a mean aspect ratio (eccentricity) of their axes equal 0.77 (0.64). Cyclones are smaller than anticyclones and prevail in both data sources. Cyclones tend to be more prevalent over shallow shelves, and anticyclones over deep water regions. Peak eddy activity is registered in June, while chl-a data also possess a second peak in April. In SST, the highest eddy probability is found along the East Greenland Current in the Nordbukta region at 76–78°N and along the West Spitsbergen Current at 78–80°N. In chl-a, most of them are observed in the central Fram Strait. The overall number of eddies with a positive chl-a anomaly, dominated by cyclones, is larger (62%) than that with a negative one (~38%). The number of eddies with positive and negative SST anomalies is nearly equal. Eddy translation velocities are 0.9–9.6 km/day (mean value 4.2 km/day). Despite frequent cloud and ice cover, MODIS data is a rich source of information on eddy generation hot-spots, their spatial properties, dynamics and associated SST and chl-a anomalies in the Arctic Ocean.

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Based on satellite data, E. huxleyi bloom contouring, quantification of particulate inorganic carbon (PIC) production and increment of CO2 partial pressure, (pCO2) in surface water were performed. 18-year (2003–2021) time series of these variables are obtained for the Norwegian, Greenland and Barents seas. The bloom areas in the North Atlantic–Arctic water are the lowest in the Greenland Sea varying from 10×103 km2 to (20–40)×103 km2. In the Norwegian and Barents Seas they reach in some years (60–80)×103 km2 and (500–600)×103 km2, respectively. The total PIC content within E. huxleyi blooms rarely exceeds in the Greenland and Norwegian seas 12–14 kilotons and 40 kilotons, respectively. In the Barents Sea, in some years, it can be up to 550 kilotons. The highest level of pCO2 within E. huxleyi blooms in surface waters in the Barents Sea was ~350 µatm. In the Norwegian Sea, pCO2 in surface waters within the E. huxleyi bloom was also close to 350 µatm, but most often it remained about 250 µatm. In the Greenland Sea there were only four years of relatively enhanced pCO2 (up to 250 µatm), otherwise remaining below the level of confident determination by our method. As E. huxleyi blooms are generally very extensive, occur throughout the entire World Oceans (and hence in sum occur all year around), this phenomenon has a potential to both decrease to some degree the role of the World Oceans as sinkers of atmospheric CO2, and affect the carbonate counter pump.

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