- Stephane Massinger
- environmental journalist
Scientists have warned that climate change could release massive amounts of bacteria as the world’s glaciers melt.
Among the thousands of microbes that can find their way into rivers and lakes are potentially dangerous pathogens.
Researchers at Britain’s Aberystwyth University said their study highlighted the need for swift action to curb global warming.
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The study included meltwater from eight glaciers in Europe, North America and two locations in Greenland.
Glaciers are huge, slow-moving masses of ice that have formed over hundreds or thousands of years. And as the planet warms, these rivers are melting at an alarming rate, causing sea levels to rise.
The Aberystwyth University team estimates that the situation could result in the release of more than 100,000 tonnes of microbes such as bacteria into the environment over the next 80 years – a number comparable to all the cells in any human body on earth.
The microbiologist Dr. Irwin Edwards said the study clearly shows for the first time the “broad spectrum” of microorganisms that live on the surface or are trapped in glaciers on Earth.
“The number of microbes released is highly dependent on how fast the glaciers are melting and therefore how much we continue to warm the planet,” he adds.
The science team’s calculations are based on the “moderate” warming scenario as developed by the Intergovernmental Panel on Climate Change, an international group of climate experts.
This will lead to an average increase in global temperatures of 2 to 3 degrees Celsius by 2100.
dr Edwards explained that increases in microbes in rivers, lakes, fjords and seas could have “significant” impacts on water quality.
But this was followed by the extinction of the microbial beak in the decades that followed, as glaciers disappeared entirely.
“Globally, 200,000 watersheds are fed by glacial meltwater, some of which are very sensitive environments that have not evolved well in terms of organic carbon and nutrients,” he said.
“There is a lot of economic activity in other countries and billions of people who depend for their livelihoods on the water that ultimately comes from these glaciers.”
“We think of glaciers as a vast reservoir of frozen water, but the key lesson from this research is that they are also ecosystems in their own right.”
He claimed that thousands of different microorganisms grow or are stored in glaciers, some of which may be harmful to humans.
“The risk is probably very small, but it requires careful assessment.”
The glaciologist Dr. Tristram Irvine-Vein said more research is needed and that “Projections of peak glacial water levels over the world’s mountains over the coming decades mean we need to improve our understanding of the state and fate of (these) ecosystems.”
“With a better understanding of this image, we can better predict the effects of climate change on ice surfaces and the biochemistry of watersheds.”
The findings, by scientists from Aberystwyth University, have been published in several scientific journals, including Nature.