Viruses frozen in Arctic ice could be slowing melting processes

How does a virus prevent ice from melting?

The presence of giant viruses inside ice appears to be inhibiting the growth of black snow algae, which is pictured above. This type of algae is notorious for causing ice melt faster, as it darkens the surface of ice and reduces its ability to reflect sunlight.

While invisible to the naked eye, viruses locked inside the ice are remarkably large, measuring about 2.5 micrometers – roughly 125 times larger than a typical virus. They’re about the same size as fine air particles, which are responsible for air pollution in most developed countries.

The supersize viruses’ genetic complexity is equally impressive, with genomes comprising around 2.5 million base pairs, compared to the 150,000 to 200,000 base pairs found in many bacteria’s DNA. Such size and complexity place them in a unique category.

However, more significant than their size is their impact on their hosts.

These giant viruses tend to infect algae that bloom on the Greenland ice sheet during the summer months. By affecting the growth of this algae, the viruses could hinder their ability to speed up ice melt.

What do the scientists say?

The discovery of supersize viruses in the Arctic is significant, as giant viruses have only been known to the scientific community for about 40 years. The first examples were found in the ocean back in 1981.

Since then, they’ve been found in a number of environments, including the human body, but never before on an ice sheet. Perini’s team discovered them by analysing the DNA from ice samples and detecting sequences that belong to giant viruses.

‘We don’t know a lot about the viruses, but I think they could be useful as a way of alleviating ice melting caused by algal blooms,’ said Laura Perini, a postdoctoral student and co-author of the study, in a press statement.

‘How specific they are and how efficient it would be, we do not know yet. But by exploring them further, we hope to answer some of those questions,’ she added. Perini and her team are now committed to finding out what roles viruses play in the icy ecosystem.

Could viruses be used for climate action?

This knowledge comes at a critical moment. The Arctic is warming four times faster than the rest of the world, and natural solutions to combat this warming could be vital in slowing ice melt.

Arctic ice is so diminishing rapidly that current predictions suggest the region could be ice-free by 2040.

The loss of Arctic ice has widespread implications, including rising global temperatures, weather extremes, endangered coastal communities, food instability, wildlife decline, and methane release from permafrost.

By understanding and potentially harnessing the role of giant viruses in controlling algae species, scientists hope to develop new strategies to mitigate the rapid ice loss and its global repercussions.

The research from Aarhus University does exactly that, presenting a new avenue for combatting climate change.

It’s possible that the continued study of giant viruses and how they interact within the Arctic environment could offer a novel pathway for preserving this important and rapidly deteriorating region.