Climate change: How important are microbes that inhabit glaciers?

New research, published in the journal Nature Communications Earth and Environment, used surface meltwater samples from four glaciers in the European Alps, as well as from Canada, Sweden, Svalbard and the western Greenland ice sheet, to study the microbes present in these ecosystems.

The new research, published in the journal Nature Communications Earth and Environment, used surface meltwater samples from four glaciers in the European Alps, as well as glaciers in Canada, Sweden, Svalbard and the western Greenland ice sheet.

As the authors' detail, the rapid melting caused by the climate crisis means that glaciers and the unique microbial ecosystems they house are "dying before our eyes", so they rush to understand them before they disappear. Some of them could be a future source of useful biological molecules, such as new antibiotics.

Microbes that inhabit glaciers

The bacteria and algae expelled by the melting ice would contribute an average of 650,000 tons of carbon per year for the next 80 years in the northern hemisphere.

The data from the study allowed us to estimate that the expelled bacteria and algae would contribute an average of 650,000 tons of carbon per year for the next 80 years in the northern hemisphere, excluding the Hindu Kush region of the Himalayas, which was not included in the sample. In addition, he points out that if carbon emissions were reduced, slowing global warming and melting ice, the mass of microbes released would be reduced by about a third.

"We are seeing glaciers die before our eyes, affecting the microbes there, with implications for us locally and globally," said Arwyn Edwards, from the University of Aberystwyth in Wales, and part of the study team. "The mass of microbes released is enormous, even with moderate heating."

According to Edwards, there is not enough data to understand the value and threat of these microorganisms. “I am often asked if there will be a doomsday pathogen melting from the glaciers. I think it's a very small risk, but it's not zero risk, so we need a risk assessment of these microbes."

Thousands of microbial species

Until recently, very little was known about the thousands of microbial species that inhabit the ice surface. For this reason, a consortium of researchers, the Vanishing Glaciers Project (VGP), is carrying out expeditions around the world to collect samples and evaluate this biodiversity.

Professor Tom Battin, from the École Polytechnique Federale de Lausanne and part of the VGP, said people should not worry about pathogens coming out of the ice. He also noted that most of the microbes did not seem to persist downstream.

Other recent virus research in Lake Hazen, Canada, suggests that the risk of viruses being transmitted to new hosts is greatest near locations where large amounts of meltwater flow.

'Harmful'

Estimates suggest that Earth's glaciers have been losing about a trillion tons of ice per year since the early 1990s, mainly due to increased melting of their surfaces.

Scientists believe that the impact of further glacial melt, including the discharge of microbes to downstream environments, may be significant.

Dr Arwyn Edwards from Aberystwyth University added: “These important findings build on much of our previous research here at Aberystwyth. The number of microbes released is closely dependent on how quickly the glaciers melt, and therefore how much we continue to warm the planet.

“But the mass of microbes released is enormous even with moderate warming. While these microbes fertilize downstream environments, some of them could also be harmful."

The Aberystwyth academics' findings were published in the journal Nature Communications Earth & Environment this month.

Keep Reading

Part 1: Cloudburst  in Ganderbal's Padabal village & unfulfilled promises