Because cow farts have no effect on the climate.
Fake meat and veganism are making strides against the meat and dairy industry under the guise of global warming or climate change. This may be news to the meat and dairy industry, but there is absolutely no science to support blaming the meat and dairy industry for global warming.
Yes, it’s true that livestock are sources of methane (natural gas). It’s also true that methane is technically a greenhouse gas that has about 20 times more heat trapping potential in an empty sky scenario than carbon dioxide.
But that’s about the end of the truth. There is no truth to the notion that livestock emissions of methane – or any emissions of methane at all – are warming the climate in any discernible way.
So how can methane be 20 times more potent that carbon dioxide yet have no meaningful real-world warming potential? The physics are really pretty simple.
Greenhouse gas theory holds that ultraviolet radiation from the Sun is absorbed by the Earth and then gets re-reradiated back to the atmosphere as infrared radiation.
But before the infrared radiation can escape into space, it is temporarily captured or absorbed by various gases in the atmosphere including water vapor, carbon dioxide, nitrous oxide and – yes – methane.
Here’s the rub, though.
There is only so much infrared radiation re-radiated back into the atmosphere, which makes sense since there is only so much ultraviolet radiation that reaches the Earth from the Sun. So the various greenhouse gases in the atmosphere “compete” to absorb the re-radiated infrared radiation. And some gases compete better than others based on their physical properties and quantities in the atmosphere.
In that competition, methane is a loser.
The chart below indicates the infrared absorption potential by the various greenhouse gases. Methane (CH4) looks like it has tremendous potential for infrared absorption – and it would in an atmosphere with water vapor or carbon dioxide.
But the reality – and what climate alarmists don’t want to admit – is that water vapor and carbon dioxide pretty much absorb all the infrared leaving none for methane to absorb. So while methane can absorb 20 times more infrared than carbon dioxide under laboratory conditions, in the real world, there is little to no infrared red leftover for methane to absorb.
Not only does methane have a hard time competing against water vapor and carbon dioxide to absorb reradiatied infrared radiation, there is little methane in the atmosphere.
Water vapor, clouds and carbon dioxide account for and estimated 95% of greenhouse gas warming. That doesn’t leave much room for methane. While carbon dioxide makes up about 0.04% (410 parts per million) of the Earth’s atmosphere, methane only amounts to about 0.00018% (1.8 parts per million).
There’s not much methane in the atmosphere and there’s not much, if any, infrared radiation leftover for it to absorb. Methane may therefore be referred to as the “irrelevant greenhouse gas.”
Why the meat and dairy industry is allowing itself to lose market share over this is beyond comprehension.