‘Impossible’ life discovery under Arctic ice could change climate science

Scientists have discovered special yet impossible life forms under Arctic ocean ice, marking a paradigm shift in the climate models.

In a research study published in Communications Earth & Environment, the researchers found the microbes called non-cyanobacterial diazotrophs under ice (NCDs) that are responsible for fixing nitrogen but are unable to photosynthesize.

According to biologist and lead author Lisa von Friesen from the University of Copenhagen, earlier it was believed that nitrogen fixation could not occur under the sea due to dark and frigid conditions.

Nitrogen fixation is a historical phenomenon that was limited to warm and tropical waters.

“We were wrong,” said study author Lisa after microbes’ discovery in the Central and Eurasian Arctic.

Historically, oceanic nitrogen-fixers were believed to be exclusive to warm, tropical waters. The first of its kind discovery in the Central and Eurasian Arctic proves it wrong.

As per researchers’ observations, although these microbes are not found with evidence of fixing nitrogen in the Arctic, based on the genetic machinery, there is an abundance of evidence that they are actively involved in the region’s nitrogen-fixing activities.

If it proves right, the discovery of these nearly-impossible microbes could change climate science globally.

According to study, the fringes of Arctic sea ice host more non-cyanobacterial diazotrophs and show higher nitrogen-fixing activity.

Having been fed on the algae, NCDs could also support the food web under sea ice.

"Because algae are the primary food source for small animals such as planktonic crustaceans, which in turn are eaten by small fish, more algae can end up affecting the entire food chain," explains von Friesen.

Moreover, more algal production could help in carbon sequestration as “the Arctic Ocean will absorb more CO2 because more CO2 will be bound in algae biomass," says marine microbial ecologist Lasse Riemann.

Given the unprecedented discovery, Riemann suggests that these nitrogen fixers must be included in the future climate models.