One also has to consider that the methane decays over a matter of decades. Other than CO2, which stays in the atmosphere until it is taken out.

So, even if methane takes a big share in current greenhouse emissions, its share in the accumulated greenhouse gases in the atmosphere will be lower.

The climate change it causes is temporary. (Disregarding runaway effects.)

https://en.wikipedia.org/wiki/Atmospheric_methane

Decades – we don't have decades to fix this.

Also, it decays into CO2, so to claim that its effects are temporary is misleading. On top of that, as long as the carbon is in a CH4 bond, it traps at least 20× as much radiation. Please don't dismiss the significance of methane emissions.

How many years do we have to fix this then? Alternatively, at what point will activists start saying we passed the point of no fix and give up their activism?

Here you go: https://croadsworldclimate.climateinteractive.org/

Honestly dude, rise above the cynicism (if that's how you meant to come across). You're a goddamn adult, and a well-educated engineer at that. Your current standard of living is at risk because of climate change (also millions of lives in poorer countries, but whatever). Spend 10 seconds on a Google search. "Activists" don't owe you any answers.

Never forget, despite what the sensationalists will tell you, climate change is very much fixable. Clean energy and better land management can and will get us there – and eventually, maybe in 200 years, we'll sequester enough carbon to get back to 350ppm. The question is about what happens in the meantime: if we act fast, we'll only get decades of food insecurity, war, and displacement, mostly in poorer countries [2]. If we delay further, we'll simply see much worse, and at home as well. But the "point of no return" rhetoric is nonsense and does nothing but paralyze people.

By the way, one of the easiest and fastest ways to catalyze at-scale solutions would be a revenue-neutral carbon tax at the source, effectively internalizing the social costs of climate change and letting the free market do its thing. (Look up "fee and dividend"; lots of folks are working on this already.)

[1] unless we hit some really unlucky runaway feedback loop, which is possible. [2] plus the disease epidemics and terrorism that come along with it – we don't live on an island.

You're the one writing phrases like "we don't have decades to fix this". How is one supposed to interpret that as anything but "point of no return" rhetoric, especially in light of that rhetoric actually being used with some frequency for the last few decades? I agree it's not helpful rhetoric, so maybe I should have aimed my comment at alarmists who use the rhetoric but who haven't fully embraced that it's too late, instead of the more general activists.

I'm fully on-board with planetary engineering projects. Those require engineering work and capital more than activism, though.

Do you want to make a prediction on the accuracy of whatever climate model you like (we can use the one you linked if you prefer) for what the temperature increase will be in 2 years, 7 years, and 12 years? We can record it at https://predictionbook.com/

Climate change is mostly no binary event. There is the risk of runaway effects, and possible extinction (though unlikely) but luckily we haven't hit those yet.

The political 2 degree goal is damage control. Climate models are complex and impacts harder to predict the more you divert from the current situation.

At 2 degrees the costs to society (social costs of carbon) far outweigh the mitigation costs. To hit the 2 degree target we have to act swiftly "we don't have decades to fix this" we are not (yet) at a "point of no return"

As green house gases are currently an externality, there will be no capital without activism.

I am too young to look back decades, but my understanding was that the "we don't have decades to fix this" guys in the 80s and 90s were more about running out of oil(and that turned out to be no problem as rising prices make more expensive extraction feasible) and that climate change as a concern only really started in the 90s (even though known long before that). And there are already damages that could have been prevented by acting swiftly in the 90s. We could have reached e.g. a 1.5 degree target. So the "we don't have decades to fix this" rethoric is fitting as ever.

I got to that point 3-4 years ago, personally. Even if it were economically and technically possible to get our act together, it has become entirely clear that the political system is incapable of acting quickly enough.

> Also, it decays into CO2…

If that carbon was already in the biosphere that’s mostly, fine long term. I worry a lot more about the carbon we keep adding to it, that wasn’t in the equation.

We should he focusing on plastics rather than methane.

The runaway effects are exactly the concern. Check out research on methane clathrates in the Mesozoic. Methane is 24x as potent a GHG than CO2.

When you see the gas flares in hydrocarbon production fields it may look like a waste (it is), but it has to be done because the alternative of releasing methane into the atmosphere is worse.

Methane contains carbon so it's not 100% temporary just mostly.

As far as I can see, those references do not mention whether they have corrected for the fact that methane is a ~20x more potent greenhouse gas than CO2. Are they counting per volume or per potency? That is an incredibly important distinction. Which, to be honest, they should have made, one way or the other.

They are in the units "greenhouse gas emissions" which corrects for the extra potency. The sad thing is that people often double-correct for such things.

Potency is typically assumed in the industry, the volume of methane is trivial compared to volume of CO2.

Random Gaurdian story puts methane : "Methane accounted for about 16% of global greenhouse gas emissions in 2015, according to the IPCC." (https://www.theguardian.com/environment/2017/sep/29/methane-...)

Wikipedia puts (with some question about the citation) methan at 4-9% of total greenhouse effect contribution, and CO2 at 9-26%. (And then water vapor way above that, at 36-72%.) https://en.wikipedia.org/wiki/Greenhouse_gas#Greenhouse_gase...

How are we producing water vapor more than say clouds?

I think the table is attributing greenhouse to gases generally, not to man-made gases; as a result, water vapor wins. (OTOH, turning clouds into drinking water at scale would be a cool way to fight global warming and deal with drought at the same time. My understanding is that storm seeding has a pretty seedy history, though.)