From a PNAS article:
The conditions of methane (CH4) formation in olivine-hosted secondary fluid inclusions and their prevalence in peridotite and gabbroic rocks from a wide range of geological settings were assessed using confocal Raman spectroscopy, optical and scanning electron microscopy, electron microprobe analysis, and thermodynamic modeling. Detailed examination of 160 samples from ultraslow- to fast-spreading midocean ridges, subduction zones, and ophiolites revealed that hydrogen (H2) and CH4 formation linked to serpentinization within olivine-hosted secondary fluid inclusions is a widespread process.
And this from a paper in Nature:
Methane (CH4) is an important greenhouse gas because it has 25 times the global warming potential of carbon dioxide (CO2) by mass over a century. Recent calculations suggest that atmospheric CH4 emissions have been responsible for approximately 20% of Earth’s warming since pre-industrial times. Understanding how CH4 emissions from ecosystems will respond to expected increases in global temperature is therefore fundamental to predicting whether the carbon cycle will mitigate or accelerate climate change.
So, “abiotic” methane production is “ubiquitous,” and methane is 25 times the greenhouse gas that CO2 is, and none of this has even begun to be entered into climate models.
Certainly some of this methane ends up in our oceans as a condensed gas; but, how much more, over this equilibrium position, does this methane get itself up to the surface and into our atmosphere?
From the accompanying Phys.Org Press Release:
Of 160 rock samples analyzed from across the world’s oceans, almost all contained pockets of methane. These oceanic deposits make up a reservoir exceeding the amount of methane in Earth’s atmosphere before industrialization, estimates Frieder Klein, a marine geologist at WHOI and lead author of the study.
“We were totally surprised to find this massive pool of abiotic methane in the oceanic crust and mantle,” Klein said.
For the first two decades in the atmosphere, methane is 84 times greater a greenhouse gas than CO2. And, guess what, they found this methance coming out of the mid-Atlantic Ridge. IOW, they can’t begin to know the extent that these methane emissions affect climate.
Anyone ready to spend 50 trillion dollars to effect changes that won’t change temperatures one twit?
But, you can become a trillionaire if you’re at the receiving end of all of this. Isn’t that good news? NOT!