News Humans are creating up to 40 per cent more methane than previously believed

Humans are creating up to 40 per cent more methane than previously believed

Researchers extract ice samples that contain methane in Greenland. Photo: NIWA
Twitter Facebook Reddit Pinterest Email

Humans are creating up to 40 per cent more methane than previously believed, leaving scientists to call for urgent action in reducing fossil fuels, a pioneering study has found.

Led by the University of Rochester in the United States, researchers from across the world, including New Zealand and Australia, found the amount of methane in the atmosphere can be attributed to humans is between 25 and 40 per cent higher than previously estimated.

Tony Bromley, who runs the world’s most accurate lab for methane testing at the National Institute of Water and Atmospheric Research in New Zealand, said the results were “worrying”.

“That’s not a good look,” Dr Bromley told The New Daily.

“Most of the methane is caused by humans. It is human-induced emissions from the burning of fossil fuels or increase in animals which produce methane.

Dr Tony Bromley in the lab in New Zealand. Photo: NIWA

“Twenty years ago, when we were looking at the numbers, we thought they were right, but because we have the ability to do this new research, we’re able to measure the amount of methane and track what caused it.

“What we are saying is, we’ve increased the methane levels, from a point that was already quite high.”

Methane is a powerful greenhouse gas and a large contributor to global warming.

Because of its ability to trap heat, the gas is much more potent than its more notorious cousin, CO2.

Last year, researchers from University of Bristol warned that if methane levels increased at the current rate, the Paris climate goal of limiting global warming to 2 degrees Celsius would be very difficult to meet.

The silver lining is that methane breaks down quickly, only spending 12 years in our atmosphere.

This means if we act soon, it will have a big effect on reductions, said Dr Bromley.

“If I’m looking for a good point, yes there is a lot, but if we stop putting it in, we’ll see an effect immediately,” he said.

Ice samples are taken in Greenland and sent to New Zealand. Photo: NIWA

“Every time we cut back on methane, stop using fossil fuels, stop using petroleum, then there’s less methane going into the atmosphere.

“We can stop it … We have control.”

Up until now, it has been impossible for scientists to determine how much of the methane is man made.

Naturally released methane often comes from soggy sources like wetlands and decaying vegetation.

And fossil methane is primarily emitted when humans extract and burn fossil fuels including oil, gas and coal.

Alarmingly, methane gas levels released from fossil fuels increased 10 per cent more than previously thought.

PM wants to transition with gas

The Climate Council’s Will Steffen said the research shows we’re underestimating how much much gas escapes when we mine it from the earth.

“Up until now the greenhouse gas emissions have come primarily from burning gas, say in a power plant. When you do that, you produce less CO2 than coal,” Professor Steffen said.

“Why this study is important is people tend to neglect that when you extract the gas, there are gases that escape from the ground [and] methane is an important one.”

scott morrison
Scott Morrison looks longingly at a lump of coal in Parliament in February 2017.

The federal government recently released a “landmark” deal with New South Wales to reduce emissions by using gas as a transitional fuel.

Announcing the project, Prime Minister Scott Morrison said: “There is no credible plan to lower emissions and keep electricity prices down that does not involve the greater use of gas as an important transition fuel.”

But this study proves just how wrong that is, Professor Steffen said.

“Gas is not the way forward,” he said.

“When you look at what we need to do to meet the Paris target, we cannot open any more fossil fuels for domestic or for export purposes.

“We need to transition straight from coal to renewables, and we can do that.”

Dr Benjamin Hmiel from the University of Rochester said although the research paints a bleak picture, it shows quick action from governments can translate to immediate results on emissions reduction.

“If we stopped emitting all carbon dioxide today, high carbon dioxide levels in the atmosphere would still persist for a long time,” he said.

“Methane is important to study because if we make changes to our current methane emissions, it’s going to reflect more quickly.”

View Comments