Wednesday, November 03, 2021

The Methane Pledge

 Yet another media headline announcement is being treated with caution by the experts. Scores of nations have signed up to curb methane emissions by 30 per cent by 2030.  The press releases suggest the initiative will reduce the expected global rise in temperatures by at least 0.2C by 2050. US President Biden said it was a “game-changing” commitment.

But climate scientists warned world leaders were using “discredited” assumptions and making “misleading” claims when promoting the launch of the Pledge at an event in Glasgow. 

 Biden said methane emissions were responsible for about half of global warming the world is experiencing today.  

However, climate scientist Piers Forster said it was “misleading” to use that metric, explaining that carbon dioxide is in fact responsible for around 80 per cent of total global warming.  

EU Commission President Ursula von der Leyen and Canadian President Justin Trudeau said methane was around 80 times warming than carbon dioxide.  

That metric is “pretty discredited”, Professor Forster explained, pointing out the UN’s climate change convention works on the basis methane is about 29 times more warming than CO2.  

Using the first metric “makes methane look far more important than CO2 than it actually is” he said.  

Professor Forster has worked with other scientists at Leeds University and Imperial College London to assess the effect of the Global Methane Pledge, using the latest climate science.  They estimated the Pledge will reduce emissions by 0.1C, not 0.2C as stated by world leaders. To curb warming by 0.2C, methane emission cuts of 50 per cent will be needed by the end of the decade, they concluded. 

A reduction of 0.1C is still “amazing”, Forster stressed, but he warned world leaders must not lose focus on the challenge of slashing CO2 emissions.  

“I’m a real fan of the methane pledge – methane’s been overlooked and gas leaks and food waste are easy wins,” Professor Forster said. “However, its needs to be CO2 AND methane – not either one or the other.”

Professor Ray Pierrehumbert, professor of Physics at the University of Oxford, agreed.

He said: “As things stand, methane is mostly just a distraction from the main job of ridding the world economy of fossil fuel burning and its associated carbon dioxide emissions.” 

COP26: World leaders accused of ‘overegging’ effect of pledge to cut methane emissions (

1 comment:

ajohnstone said...

Ireland's Taoiseach Micheál Martin said Ireland would sign a pledge to cut methane emissions by 30 per cent, but he stressed that the figure was a global target rather than a national one.

“We will contribute globally to a global reduction. It’s a global pledge, it’s not country-specific. We will develop our climate action plan which will give our specifics in respect of each sector,” he said.

Approximately 93% of Irish methane emissions come from livestock-based agriculture