Hidden Production: On the Importance of Pelagic Phytoplankton Blooms Beneath Arctic Sea Ice
According to model results, most primary production in the Arctic Ocean occurs under sea ice that is at least 50% in concentration.
Current observational estimates of the primary production in the Arctic Ocean may be significantly underestimated, due to the importance of under-sea ice production. Increased light transmission, due to the removal of sea ice, more extensive melt ponds, and thinner sea ice, is implicated as the main cause of increasing trends in primary production.
At present, there are no Arctic-wide observations and estimates of primary production beneath Arctic sea ice because it cannot be measured by satellite and is difficult to access via ship. Utilizing our state-of-the-art Arctic system model, we have quantified the primary production beneath Arctic sea ice and our findings show that the majority of production occurs in waters covered by at least 50% ice. This analysis represents a major revision of the traditional view that no significant biomass is produced in sea-ice covered waters. Our results are consistent with recent and very limited (in space and time) observational studies; however, we provide information for the entire Arctic Ocean, including increasing trends in production over the time period of 1980-2018.