DATE: February 6, 2018

SNIP: Researchers from Aarhus University have measured a new world record: Small ice algae on the underside of the Arctic sea ice live and grow at a light level corresponding to only 0.02% of the light at the surface of the ice. Algae are the primary component of the Arctic food web and produce food far earlier in the year than previously thought.

The general view has been that ice algae do not obtain sufficient light for growth when they are covered by a more than 30-50 cm deep cover of snow and ice. The new measurements completely change that view and show that ice algae may play an important role much earlier in the spring in the Arctic than hitherto assumed.

Temperatures are rising in the Arctic. When the snow on top of the ice gets warmer, the algae residing on the underside of the ice receive more light. This may significantly impact the growth of the algae and the extent of the ‘spring bloom’. This new knowledge must be considered in the puzzle of how the Arctic will respond to a warmer world