There are more microbes in the human body than there are people on Earth.
These tiny organisms help digest food, neutralize toxins and can even help control greenhouse gas emissions. Despite making life possible, some scientists say microbes are missing from climate models and solutions – and that needs to change.
Microbes, also called microorganisms, refer to anything living that we can’t see without a microscope, including viruses, bacteria, and fungi.
“They support all life on Earth,” said Lisa Stein, a microbiologist at the University of Alberta.
“Without them, we would definitely be dead.”
Microbes help control carbon and nitrogen cycles, including the production of methane – a gas 86 times more potent in warming the climate than carbon dioxide over a 20-year period.
Over the past two centuries, concentrations of methane in the atmosphere have more than doubled, according to the U.S. Environmental Protection Agency.
However, the gas remains in the atmosphere for about a decade before quickly disappearing, whereas carbon dioxide can persist for centuries.
Sources of human-caused methane emissions include oil and gas systems, landfills, agriculture, coal mining, and wastewater treatment.
Canada’s federal government has a proposed plan to reduce methane emissions in the oil and gas industry by more than 75 percent by 2030.
Active radio8:17 a.m.Microbes and climate change
While it’s important to control methane emissions from industry, Stein said, it’s not the only source of greenhouse gases.
“It’s not going to stop methane emissions. Probably not much, because the majority of those sources are land use-based,” she said.
About a third of total methane emissions come from wetlands, according to NASA map data.
Wetlands have waterlogged soils and permafrost, making them carbon sinks. But as the climate continues to warm, wetland soils also warm or may flood and permafrost melts, causing more carbon to be released into the atmosphere in the form of methane.
Another problem, Stein said, is that methane emissions from natural sources, like wetlands, are generally not included in climate modeling, making future projections less reliable.
The difficulty is that the models primarily use chemistry and physics, Stein said, and don’t always include the effect of living systems, like microbes, which are constantly growing, changing and dying.
“It’s so dynamic.”
Another difficulty is getting people to care about something they can’t see.
“It’s easier to show melting ice and hungry polar bears than it is to show bacteria,” Stein said.
Although the federal government recognizes natural sources of methane emissions, a spokesperson for Environment and Climate Change Canada said in an email to CBC that these areas are not amenable to management or regulation.
While some microbes emit methane, others consume it.
Methanotrophs are microorganisms that eat methane and remove it from the atmosphere.
In recent years, there has been growing interest in finding a way to use these organisms to combat climate change, said Mary E. Lidstrom, a microbiologist at the University of Washington.
The main challenge is scaling up, so the bacteria can remove enough methane from the atmosphere to make a difference.
“It has to be profitable for commercial investors,” she said.
However, a company could have fixed this problem.
Windfall Bio, an American startup, is piloting a program to sell methane-eating microbes present in the soil to farmers. The microbes are then “fed” methane from animal manure, using a system of tarpaulins and pipes, and in turn make fertilizer that the farmer can use on his crops.
“It’s about getting living organisms to do what those living organisms evolved to do,” said Josh Silverman, CEO of Windfall Bio.
Microbes can also be used to clean up waste.
A Cambridge study has found that bacteria found naturally in European lakes thrive by eating pieces of plastic bags.
The bacteria breaks down the carbon compounds in the plastic and uses it as food for growth.
While this is an unlikely solution for waste due to the scale of plastic pollution, said Andrew Tanentzap, one of the researchers behind the research, it nonetheless highlights demonstrates the resilience of nature.
“Nature might have the solution,” he said.