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Tiny microbes hidden in the soil are one of the major amplifiers of global warming.

But researchers are unsure whether these microbes are slaves to their environment or the cause of climate change.

Now, scientists from the U.S., Sweden and Australia, claim to have evidence that a single species of microbe found in Sweden may be driving global warming.

Scientists from the U.S., Sweden and Australia, claim to have shown that a single species of microbe found in Sweden may be driving global warming. The researchers installed special instruments for measuring methane changes using Plexiglas chambers that trap the gases emanating from the soil

The discovery could help scientists improve their simulations of climate change by including data on how microbes control the release of gases, such as methane.

Earlier this year, scientists found a single species of microbe in permafrost soils of northern Sweden that had begun to thaw under the effect of globally rising temperatures.

Researchers suspected that the microbe played a role in global warming by releasing vast amounts of carbon stored in permafrost soil close to the Arctic Circle in the form of methane.

Methane is a powerful greenhouse gas responsible for trapping heat in the Earth's atmosphere.

But the actual role of this microbe - dubbed Methanoflorens stordalenmirensis, which roughly translates to 'methane-bloomer from the Stordalen Mire' - was unknown.

The discovery in Sweden could help scientists improve their simulations of climate change by including data on how microbes control the release of gases, such as methane

The international research team installed automated chambers that measure greenhouse gases emanating from the soil as microbes metabolise nutrients previously locked up in the permafrost soil

The new research pins down the role of the new microbe, finding that the amount of Methanoflorens, should help to predict their collective impact on future climate change.

'If you think of the African savanna as an analogy, you could say that both lions and elephants produce carbon dioxide, but they eat different things,' said senior author Scott Saleska, an associate professor at the University of Arizona.

'In Methanoflorens, we discovered the microbial equivalent of an elephant, an organism that plays an enormously important role in what happens to the whole ecosystem.'

DID MICROBES CAUSE THE WORST MASS EXTINCTION IN HISTORY?

Climate-changing microbes, known as Methanosarcina (pictured), may have caused the biggest mass extinction in history

The worst mass extinction in Earth's history - long before dinosaurs roamed the planet - was caused by microbes, according to a recent study.

The tiny organisms suddenly began belching out the greenhouse gas methane - which is about 20 per cent more potent than carbon dioxide - some 250 million years ago.

Fumes spurted from the oceans wiping out 90 per cent of all species, from snails and small crustaceans to early forms of lizards and amphibians in less than 20,000 years.

The 'Great Dying' occurred more than 252 million years ago - long before dinosaurs lived roamed Earth - at the end of Permian era.

In the past asteroids, volcanoes and raging coal fires have been blamed but the finger is now being pointed at tiny microbes called Methanosarcina.

These spewed enormous amounts of methane into the atmosphere, dramatically altering the climate and the chemistry of the oceans.

Unable to adapt in time, countless species perished and vanished from the Earth.

Alarmingly, the same effects are starting to happen today as a result of global warming caused by carbon emissions. 

The study revealed that because of these microbial activities, all wetlands are not the same when it comes to methane release.

'This has been a major shortcoming of current climate models,' said lead author Carmody McCalley, at the University of New Hampshire.

'They assume the wrong isotope ratio coming out of the wetlands, the models overestimate carbon released by biological processes and underestimate carbon released by human activities such as fossil-fuel burning.'

To study microbes, researchers drive cores into the ground at Abisko National Park in northern Sweden

One of the big questions facing climate scientists, according to Professor Saleska, is how much of the carbon stored in soils is released into the atmosphere by microbial activity.

'As the "global freezer" of permafrost is failing under the influence of warming, we need to better understand how soil microbes release carbon on a larger, ecosystem-wide level and what is going to happen with it,' he said.

'For years, there's been a debate about whether microbial ecology 'matters' to what an ecosystem collectively does,' added Virginia Rich from the University of Arizona.

'This work shows that microbial ecology matters to a great degree, and that we need to pay more attention to the types of microbes living in those thawing ecosystems.'

Projected temperature change from 2081-2100. One of the big questions facing climate scientists, according to Professor Saleska, is how much of the carbon stored in soils is released into the atmosphere by microbes