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Highlights • Satellite estimates of ocean primary productivity (i.e., the rate at which marine algae transform dissolved inorganic carbon into organic material) showed higher values for 2020 (relative to the 2003-2019 mean) for seven of the nine investigated regions (with the Sea of Okhotsk and Bering Sea showing lower than average values). • All regions continue to exhibit positive trends over the 2003-2020 period, with the strongest trends in the Eurasian Arctic, Barents Sea, and Greenland Sea. • During July and August 2020, a ~600 km long region in the Laptev Sea of the Eurasian Arctic showed much higher chlorophyll-a concentrations (~2 times higher for July and ~6 times higher for August) than the same months of the multiyear average (2003-2019), associated with very early loss of sea ice in spring and summer (see essay Sea Ice).
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This content will become publicly available on December 10, 2025
Arctic Ocean Primary Productivity: The Response of Marine Algae to Climate Warming and Sea Ice Decline
Arctic marine primary productivity (the conversion of dissolved inorganic carbon into organic material by photosynthetic organisms) forms the foundation of the marine food web and plays a critical role in global carbon cycling. It is highly sensitive to changes in sea ice cover (see essay Sea Ice), ocean temperature (see essay Sea Surface Temperature), and nutrient availability, all of which are altered by ongoing climate change. Marine primary productivity in the Arctic varies significantly across different regions, influenced by local oceanographic conditions and the timing of sea ice retreat.
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- Award ID(s):
- 1917434
- PAR ID:
- 10588065
- Publisher / Repository:
- NOAA
- Date Published:
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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