Over 100,000 tonnes of microbes – yep, you read that correctly – could come flooding out of melting glaciers in the wake of the climate crisis, according to a new analysis. Given that this scenario will involve the release of over a quintillion different microorganisms, it’s safe to bet that some may have the potential to be disease-causing germs.
Scientists at Aberystwyth University in Wales looked to work out how much microbial matter could be released due to the melting of eight glaciers across Europe and North America, as well as two sites in western Greenland.
Even under moderate climate change, they estimated that around 2.9 × 1022 cells would be released into the surrounding environment. This is roughly the equivalent of an average of 0.65 million tonnes per year of cellular carbon, which includes microbes, being dumped into the world’s ecosystems across the Northern Hemisphere over the next 80 years.
“The number of microbes released depends closely on how quickly the glaciers melt, and therefore how much we continue to warm the planet. But the mass of microbes released is vast even with moderate warming. While these microbes fertilize downstream environments, some of them might be harmful as well”, Dr Arwyn Edwards, study author and biologist from Aberystwyth University, said in a statement.
“Melting glacier ice surfaces host active microbial communities that contribute to melting and biogeochemical cycling, and nourish downstream ecosystems; but these communities remain poorly understood”, commented Dr Tristram Irvine-Fynn from Aberystwyth University.
“Over the coming decades, the forecast 'peak water' from Earth's mountain glaciers means we need to improve our understanding of the state and fate of ecosystems on the surface of glaciers. With a better grasp of that picture, we could better predict the effects of climate change on glacial surfaces and catchment biogeochemistry”, added Irvine-Fynn.
Glaciers are known to harbor an array of ancient viruses, many of which are unknown to science. Whilst they’re locked in ice, they pose little threat to us or any other part of the ecosystem. However, if this ice melts, it opens the opportunity for viruses to “jump” into a host – whether it's humans, another animal, a plant, or fungi – and continue to replicate and spread.
With rising global temperatures linked to climate change, the risk of thawing glaciers and the exodus of microbes is becoming all the higher. Just last month, a study concluded that the climate crisis and thawing glaciers are upping the risk of spillover from novel viruses - and could potentially even start the next pandemic.
Much of this remains hypothetical for now, but it’s a problem that has already flirted with the world. In 2016, dozens of people fell sick with anthrax in the Yamal Peninsula in Russia. This outbreak was blamed on a heatwave that had melted permafrost in the area and exposed an infected reindeer carcass in the Siberian tundra.
As this new study shows, anthrax rearing its ugly head in the depths of Siberia could just be the tip of the iceberg.
The new study was published in the Nature journal Communications Earth & Environment.