According to this article the correct answer is 20. That’s still over an order of magnitude difference. It still doesn’t change the priorities much, it means you can leak 40% more methane from a system before it’s worse that coal, but we aren’t usually measuring these sorts of problems in 2 decimal points to begin with.
This is also similar to meat production emissions. Most of carbon emissions in meat productions are of carbon which was captured from the air as a part of the production cycle, by the plants which feed the cattle.
The narrative is extremely misleading.
After how long? A half-life of a decade, as I understand it? Not exactly the order of magnitude of luxury time we have to spare.
> Even if it did increase warming more than CO2
"Even if it did" is strange wording for an established fact. Do you write "even if the sky was blue"?
> once methane emissions reach a steady level, reducing methane emissions won't change a thing
It's kind of really, really important how high that "steady level" is and how fast we'd reach it though, no? We're not just worried about life 1,000 years from now. We're worried about life 20 years from now.
> The narrative is extremely misleading.
I find this statement strange after reading your comment.
(Update: In hindsight I'm not sure you were talking about methane emissions in general or about methane from meat production. Here, I'm focussing on the latter. Meanwhile, fossil methane is of course a huge problem.)
As for the second part of your question: When it comes to meat production, we have already reached the steady state.
As for the first part: Yes. But it is not that high. Let's say the total amount of greenhouse gases in the atmosphere due to cattle (and rice and other types of agriculture) account for a fraction X of the world's yearly emissions. (In Germany, for instance, X = 0.06, i.e. 6%.) Let's assume for simplicity the remaining emissions are exclusively due to fossil fuels and all emissions are the same every year. Let Y be the fraction of agricultural emissions relative to fossil emissions, i.e. Y = X/(1-X). (= 6.4% for Germany)
Then, after N years, the amount of greenhouse gases in the atmosphere due to agriculture, relative to the amount of greenhouse gases in the atmosphere due to fossil fuels (burned during that timeframe) will be Y/N. This is because agricultural greenhouse gases in the atmosphere will stay constant – because we're in a steady state – but greenhouse gases due to fossil fuels will keep on accumulating.
Putting e.g. N=20 yields Y/N = 0.3% (for Germany). N=100 yields 0.06%.
In short, the amount is negligible. Fossil fuels are a real problem when it comes to climate change, agriculture is not.
Methane from fossil fuels is a problem, however.
Doesn't matter, if we keep the number of heads of cattle constant, the methane from them in the atmosphere will be constant.
If we keep using the same number of ICE cars otoh, the CO2 from them in the atmosphere will keep increasing. We would have to drop the number of ICE cars to 0 to stop the increase.
There are two directions to look at it: convincing yourself via a convincing story, or convincing yourself via a convincing calculation.
The story they tell defies basic thermodynamic intuition, and seems to skip over all the parts that would put the narrative in doubt.
The premise is that greenhouse gases absorb black body radiation from the surface.
First of all, greenhouse gas is a bad name, greenhouses warm because of air convection. So the "greenhouse" intuition they try to abuse is misleading.
Secondly, think about this thought experiment: a layer of pure CO2 gas covers the lowest layer of air near the surface. By how much would that get warmer compared to air? The answer is there won't be any difference. That's because the surface and the air near it are at the same temperature, so they emit exactly the same amount of energy. All systems with same temperature are at an equilibrium.
So what can possibly cause warming is only the effect of the difference in temperatures between the CO2 gas and the surface. Which should only be significant in higher altitudes. Which have much less CO2 because it is heavier. And it's also not clear, in this situation, in which direction the weather near the surface will change.
But then you realize there are also effects of increasing methane / CO2 which decrease warming. The most obvious effect is that they have higher heat capacity. Heat capacity goes together with absorption: the absorption is possible only because the molecules have more degrees of freedom to vibrate. So it's usually around the same order of magnitude. And higher heat capacity means faster cooling from convection and it means the air requires more energy to heat up. In fact, you can think of the entire climate change claim as a statement about the entire earth heat capacity.
So I'm entirely unconvinced by the story. But that should've been OK because there are detailed calculations. There are models.
Except these models are dumpster fire. You can download some of them from NASA's website and judge the quality of code for yourself. Old fortran code, all the models copy code from each other, many things which aren't constant physically are constant in the code, functions full of tens of "if else" statements whose physical validity is highly in question.
But those models should've been tested? Except they don't. There's no way to test them. From basic software engineering perspective, it is insane to trust these things to make the kind of trillion dollar decisions they make.
But all models point to climate change! Well they all copy code from each other. But that's not the only problem. They are all thermodynamic simulations which substitute the full state of the system with average states.
In other words, they all, by design, underestimate the entropy of the system. And thermodynamic energy is entropy times temperature, and since they get the energy right (just the sun) you expect them all to get higher temperature. So it is actually expected from all simulations to overestimate warming.
There are also other glaring counter intuitive things about the narrative. Somehow CO2 effects continue to work slowly over decades, and the system doesn't reach an equilibrium with the current levels of CO2 until decades ahead.
This is completely against normal thermodynamic intuition. Meta stable states exist, yes, and there are out of equilibrium systems. But usually the reason for systems not reaching the more stable state, is that their fluctuations are too small. In this case, the fluctuations are much much bigger than the supposed stable state change. We're talking about barely a degree change over decades in systems that fluctuate by several degrees daily. It makes no sense to claim their equilibrium will only be reached in decades while their fluctuation exceeds the difference to equilibrium daily.
Methane degrades to C02 in 1-1 proportion. So at any time, if more atmospheric carbon is concentrated as methane than as C02 then the greenhouse effect will be stronger at that time (because methane is a stronger GHG). If agriculture removes 1 unit of C02 from the atmosphere (from feedstock) and emits 1 unit of methane (from cow) then total atmospheric carbon is unchanged but the proportion of methane, and therefore the total GHG effect, is increased at that time. Summing over time, and you get an increase in overall heat that has been trapped.
It's not like mammalian herbivores are a recent invention. If a constant amount of mammalian herbivores in the world would cause a constant acceleration of greenhouse effect then the greenhouse effect would have increased exponentially for millions of years already. That has not been the case.
If you increase the number of mammalian herbivores in the world then the greenhouse effect will increase for about a decade because of increasing levels of methane. After a decade, the methane level (and therefore the greenhouse effect) will have found a new (higher) equilibrium and no longer increase.
This is not correct. We are already in a steady state. Methane levels due to cattle are already at their maximum (given a fixed amount of cattle).
At any point in time, gras will absorb some CO2 from the atmosphere, cattle will convert some gras / carbon into methane and emit the latter into the atmosphere, and some methane in the atmosphere will decompose into CO2. This is a continuous process, that's happening every second, and if the amount of cattle is kept constant, there is a maximum amount of methane that you can reach in the atmosphere as well as a maximum amount of CO2. After all, the total amount of carbon involved in the process is constant – energy conservation dictates that mass doesn't appear out of nowhere.
In fact, since we've been doing agriculture for a time much longer than the time scale in which grass grows, a cow digests grass or methane decomposes into CO2, this whole closed loop has already settled into a steady state: At any point in time, the amounts of methane and CO2 in the atmosphere due to cattle are constant. The resulting radiative forcing will thus stay constant, too.
Source? I understood that the long-term radiative forcing of methane was lower than CO2, which is incompatible with this claim.
The fertilizer contributes nitrogen and other minerals. Eliminating agricultural emissions should involve non fuel nitrogen fixation, not methane reduction.
Methane = increase in Co2 Reducing methane = no effect But reducing Co2 yes? Why wouldn’t reducing methane change anything? Following your logic reducing Methane is reducing Co2, no?
By that logic the only climate change relevant source of greenhouse gases are ones that introduce new ones into the circle, which is pretty much only burning fossil fuel.
It's a pretty old argument that holds some truth, (the fossil fuels are the biggest issue) but is also been debunked by people much smarter then me
Come on.
How does:
> reducing methane emissions won't change a thing, compared to CO2 emissions.
Follow from:
> once methane emissions reach a steady level
If we removed literally all methane from the atmosphere, this would be equivalent to reducing carbon dioxide concentration to 380 ppm. This would bring us back to climate of 2005. By any reasonable measure, climate in 2023 is not significantly different than the climate in 2005 (eg. you’d hardly be able to observe any difference without making a lot of very careful measurements, you wouldn’t “feel” any difference on your own skin).
And that’s if we remove literally all methane. Most of the methane in atmosphere is a result of natural processes, not caused by human activity. Thus, if we stop all methane emissions caused by human activity, we can maybe at best slow down climate change by 10 years. In terms of practical effects as felt by human beings, this is accurately described as “won’t change a thing”. Actually, to be more specific, slowing climate change by 10 years won’t make any difference, but stopping all methane emitting activities would be tremendously negative to human flourishing.
https://cleantechnica.com/2021/02/06/a-differential-equation...
This is because the methane is being converted to CO2 at a relatively quick clip.
The timescale for CO2 is larger-- centuries.
In terms of climate change it’s not a 10 years thing and then methane instantly swaps, it’s a second by second thing where a percentage of existing methane is constantly converted. In steady state new methane from say cow farts 1:1 replaces methane from past cow farts being transformed into CO2. The only difference is an atom of CH4 at 16.043 grams per mol weigh less than an atom of CO2 at 44.009 grams per mol. Though many sources of CH4 start by extracting atmospheric CO2, natural gas leaks don’t.
The critical difference is if we cut net CO2 and hold methane steady the atmosphere stops warming, where cutting methane and CO2 would actually cool the atmosphere.
Put another way NEW sources of methane are different because it takes multiple years to reach an equilibrium. In the first years they have a very big impact, but eventually it falls off until eventually a constant source of CO2 may actually have a larger impact.
I have a paper I’m (very slowly) working that argues that these figures may be too low. Our current model of CH4 emissions and natural destruction assume a lifetime of 9-10 years in the atmosphere. The problem is if you do some simple stoichiometry, net emissions are not enough to account for the roughly 4 Gt of excess CH4 in the atmosphere.
I’m hoping my math is wrong.
It’s a bit like calculating if I’ll die of cancer. If you could protect me from everything you might be able to know that I’d die of colon cancer at 75. But here I am breathing weird dust and walking a route that starts on city streets and driving X miles a year and you just don’t know what’s gonna get me.
The question I am investigating is an input to such calculations; I am not qualified to estimate the impact.
Cow methane is on the order of human population, so it matters.
It's also the enormous methane output of the cattle industry. There are thirty million cows in the US alone. Each is producing 150 to 300lb of methane per year.
http://www.museumgolling.at/wp-content/uploads/2022/09/9_Sch...
These wisent remains from alpine caves are all from sites now in the subalpine to alpine zone. From this it can be concluded that the beech limit but also the forest line during the »wisent time« (6,000 to 1,200 years before today) was much higher and the average summer temperature had to be at least 3 to 6 °C higher than today
Oaks (Quercus) at an altitude of 1,450 metres around 2,000 years ago also indicate a climate approximately 4 to 7 °C warmer than today
There's a lot of evidence pointing in the same direction.
https://www.nature.com/articles/s41598-020-67281-2
This record comparison consistently shows the Roman as the warmest period of the last 2 kyr, about 2 °C warmer than average values for the late centuries for the Sicily and Western Mediterranean regions.
Yet according to scientists, "Temperature rises over 2 degrees could bring catastrophic and potentially irreversible impacts, including pushing three billion people into chronic water scarcity."
https://edition.cnn.com/2023/01/30/world/global-warming-crit...
It is not comparable to the current system with domesticated animals at all.
Do you also propose we exterminate every wild deer, elk, moose, buffalo, hippopotamus, elephant, giraffe, etc?
It is not.
Domesticated cows make up approximately 35% of the world's mammal biomass. That's the same as humans. All wild land animals combined - all the ones you mentioned and many more - make up around 2%.
One source: https://ourworldindata.org/wild-mammals-birds-biomass
The domesticated chicken is, for example, by far the most common bird with a population about 15 times larger than the second.
Humans make up between 30-40% of land mammal biomass, wild animals around 4% and domesticated animals make up the rest.
We have altered the ecological balance to an insane extent. Animal husbandry use almost 80% of arable land.
The wild animals are also a part of a circular ecosystem. They are, in contrast to domesticated animals, carbon neutral in most cases.
I am writing this on a slow GPRS connection, so I can't provide you with sources, but they are readily available. Both papers and news coverage. I managed to get into this page, but that is all: https://ourworldindata.org/wild-mammals-birds-biomass
IIRC (but I am way less certain of this) there's also extra issue with methane degrading into not only CO2, but also water, and in a place where they increase the greenhouse effect rather than reducing it ?
P.S.: Also water vapor is an extremely powerful greenhouse gas... but I have no idea which fraction of water ends up in this phase under these conditions, nor how long water lasts there...
P.P.S.: Oh, also, I just remembered : CH4 (+X O2) => CO2 + H2O, is just one of many reactions that happen... IIRC this is also where the ozone layer is and all of these ingredients and products all have an effect. But in the end it's all oversimplified into CO2 has this greenhouse effect, and CH4 that one - by the climatologists ?
(All of this from climatology 101 that I had to take a decade ago, because there was no other option for a remote physics degree...)
But lots of people will say it does (the climate deniers).
I had hoped by now humanity would be moving deeply into rationality, but we're still just as emotion-driven as ever. We come by it honestly since our neurology is tuned to handle most (or maybe all) decisions subconciously and then have our conscious/rational mind justify the decision after the fact, but I do believe that by understanding our biology and implementing systems/approaches to combat it, we could become a highly logical species. There is still some hope on the horizon. Live long and prosper my friend.
This research shows that the mechanism of action was misunderstood all this time. What else hasn't been researched enough and has simplistic assumptions baked into the climate models?
That shockingly simplistic models and the barest of data don't actually have predictive power wouldn't surprise people in any other scientific discipline, but it will certainly be cause enough for this subject, to have this comment voted into oblivion....
Questioning the accuracy as a form of dismissal raise the question of what level of accuracy you'd want before accepting the results, and what level of accuracy any countering research should have. Research like this paper also has margins of error, are often single studies or analysis and therefore aren't proven to be accurate themselves. Science evolves all the time, a large amount of the science we experience or rely on day to day cannot be fully modelled with high accuracy but we don't discount reality because the models don't match it.
We just watched with front row seats what happens when once trusted scientific authorities rely on poor data, poor communications, and poor models. The general populace starts to distrust and reject them. This is the danger of every apocalyptic climate prediction that fails to come to pass. The desire to scare people into action only tends to push people into distrust and indifference.
I think climate change is a problem (not a crisis) but it's important to note that if a scientist questions climate science, he becomes a pariah. In such an environment, it's hard to know how much confidence we should have in consensus.
> Models have for a long time shown that the overall global temperature will rise and observations over the years have proved the models reflect reality. Are all models 100% correct with predictions? No, but the trend the models show is proven, even if there is a margin of error which is typically always acknowledged during modelling.
My understanding is that we observe some climate trend over N years and then select the best model proposed in the past. This is where the "oil companies knew about climate change!" accusation comes from. But it's much harder to select the model before taking the measurements and climate models have obviously performed much worse at that.
As a climate scientist myself, I can tell you this is untrue and a harmful legend. As climate science is mostly atmospheric physics, biology and chemistry, it's pretty much very easy to disagree with anyone if you have a good argument supported by data. If you have strong scientific arguments, it does not matter even if the whole world is against you. On the contrary, this will likely make you famous and secure your career. Scientists (at least the curios ones) love to be proven wrong.
EDIT: spelling
People who have never done science really like this idea of the general scientific community being some sort of secret society that agrees to support eachothers ideas.
If you put 5 scientists in a room, you can't get them to agree on >anything<. The idea that disagreement is enough to get you outcast from "science" is complete nonsense.
The interesting part is people clinging onto anything calling that impending climate catastrophe (or its human cause) into question.
Individual subjective short-term benefits outweighing rationally obvious mid- to long-term consequences is usually considered the domain of teenagers. Or of people living in very uncertain (life-threatening) circumstances, devaluing any future considerations.
Either way, those opinions can't carry weight in such a context, as their reasons share no common domain of validity with global long-term considerations.
The requirement for the math being absolutely "spot-on" in this case is extremely high.
Is it?
Or perhaps a "scientist" has spotted a suspected cancer in your brain but they can't quite pinpoint whether it's a 20x increase from normal size or a 28x increase. Based on the 28 assumption, you'll be in a wheelchair within seven years, but it might also be ten years. It's entirely preventable by doing the surgery but that costs money today plus minor lifestyle changes. Before doing a costly operation and bothering with, say, a daily pill and no alcohol, one could choose to wait while they refine their equipment over the next decades and then measure again before taking serious action. Can't trust dem scientists anyway, maybe it wasn't a problem in the first place.
That's the logic I'm seeing here. A "times worse than CO2" value for one of the elements might have been off by 30% so we should just assume nothing is wrong in the first place and not change our society away from burning carbon. Maybe it's just a coincidence that ~five of the past ten summers are the hottest of all the summers whose temperature we've measured... yeah I agree: maybe. It's a possibility, no matter how remote. But I'd rather not wager with billions of lives impacted by the outcomes that are part obvious (sea level rise) and part the prediction from yet more models. We needed to act yesterday if the models are anywhere near the truth and it's going to get exponentially harder to fix the longer we wait (because reducing emissions year-on-year is a lot easier than cutting+capturing at a moment's notice). If it turns out to be a dud, we can continue to dig up the remaining oil and have a big feast, everyone happy. If not, it's a good thing we acted and we're probably still not going to be able to prevent some level of habitat damage for the species we call human, but at least it won't be as bad as when we wait for more precise information on a problem where the conclusion remains unchanged.
(That's besides the healthy years of life provided by having cleaner air; I don't know how that would compare against e.g. cobalt mining.)
And that argument works better in reverse anyway: we're talking about a trend implying large parts of the planet becoming uninhabitable for present levels of human population within a relatively short time frame (which will also have an effect on economic activity!). If contrarians really have a good faith belief that this trend is caused by some other factor and will be self correcting, perhaps they could deign to specify their own testable assumptions and make their own model...
I'm not sure what sort of model you used to arrive at this vague estimate, but:
Even if you assume AGW science is completely wrong and the effect is zero, humans have to move from fossil fuels to renewables/nuclear in that timeframe anyway, because we have 47 years of oil left. Whether it's 20 years or 80 years, still needs to happen.
Anyways, the fundamental assumption of most models—-that humans are behind climate change—-has not been sufficiently evaluated or tested. I find starting with that assumption unscientific.
If scientist make 100 forecasts based on current models they won't all be spot on. It might turn out that say 85 of them turn out to be pretty close, 5 of them turn out to be wrong in that things actually turned out worse than the models forecast, 5 of them turned out better than the models forecast, and 5 of them didn't happen at all.
The "deniers" look at those last 5 or 10 and dismiss the models and all conclusions from them as worthless, ignoring that the models got it mostly right and that the things they got wrong are nowhere near important enough to change the overall result. They at most just change the timeline a little.
How bad climate change will be, yeah I suppose there is a little fuzzyness there. But given how bad it COULD be (think: complete extinction of humanity, or an end of civilization) we can't really wait around not doing anything while we try to develop a perfect model.
And the levels of CO2 etc. have changed as well, during time periods when it could not possibly have been blamed on humans.
I grew up in Canada, in an area with lots of farms... and I remember the high school trips to different geographical features such as moraines which are the residue of glaciers from long ago.
What caused those mile-thick glaciers to melt, given the low levels of human population and the low levels of human technology?
Yes, the average temperature of earth has chaged vastly over its history, giving different levels of habitability.
At this time, we're in a really good spot for habitability, and we are seeing that we are slipping out of it.
There is evidence that some of the temperature change could very well be human made, and thus easy to stop (compared to, say, the emissions of volcanoes).
For some reason you argue that nothing should be done, because nothing was done in past massive climate changes, which resolved in mass extinctions.
Is anything I'm saying wrong?
If you really want to criticise the models, demographic hypotheses are far more questionable than anything having to do with methane by the way. Population growth was widely overestimated in the 90s for example and might still be. Plus the impact of an aging population and immigration becoming the main factor of population growth in the USA, Europe and China isn’t really well studied. This is partially voluntary by the way as it quickly leads to unsavoury questions.
https://ourworldindata.org/world-population-growth
If modellers were caught by surprise by this then they are clueless. But they weren't because population doesn't factor into models. They go straight from projections of CO2 levels, which have also grown at a constant rate:
https://gml.noaa.gov/ccgg/trends/
So it's not clear why you bring up population growth. It's not relevant.
>> there is undeniable evidence for human emitted CO2 having an impact
What is it and how is this impact measured in an undeniable way. It can't be temperatures because they don't track CO2 levels.
Did you actually look at what you linked?
The main graph is only China and India and already shows a net inflection for China in the past few years. It will keep slowing. Read about population-lag effect.
The second graph nicely confirms that contrary to what you pretend population growth has started slowing globally.
There is no consensus about how much it will slow and when the peak will be reached. IPCCC had to adjust their hypotheses in the past because the lowest credible estimation where falling outside the lowest considered by the first climate model and some specialist argue we should look at even lower prediction. People in developing nations have stopped having large families faster than we thought.
> So it's not clear why you bring up population growth. It's not relevant.
If you don’t see how population size affects consumption, production and in fine pollution, I can’t do much for you.
> What is it and how is this impact measured in an undeniable way. It can't be temperatures because they don't track CO2 levels.
You are clearly arguing in bad faith or are clueless about the research surrounding climate change. In both case, I think it would be a waste of my time arguing further.
https://arstechnica.com/science/2012/12/ipccs-climate-projec...
Similarly, Dr. James Hansen (director of NASA's Goddard Institute) testified before Congress based on his 1988 study predicting global warming and his numbers were very close to what we saw over the subsequent 3 decades:
https://www.theguardian.com/environment/climate-consensus-97...
This research shows that one variable might be 30-40% smaller but the impact of that is clearly still within the margins on reports from 3 or 4 decades ago, so perhaps consider that the fossil fuel-funded sources telling you that the models are “shockingly simplistic” are not being entirely honest about their motives.
That by itself doesn't tell us that they understand the climate though. Remember that previously they were extrapolating a cooling trend into an ice age. Anyone can extrapolate a linear trend forward on a graph into a disaster zone territory, but that doesn't imply real understanding.
Researchers got some things right, other things wrong. What we have seen historically is that the pessimistic estimates of scientists have matched reality better than the optimistic estimates. Scientists have actually under estimated the effects of climate change.
I wasn't aware of this, but it also sounds hard to prove so I'd be very interested in such a study having been done. Or do you mean for climate change specifically? (That seems much more manageable to meta-analyse)
https://www.nature.com/articles/d41586-022-01192-2
Climate simulations: recognize the ‘hot model’ problem
Users beware: a subset of the newest generation of models are ‘too hot’ and project climate warming in response to carbon dioxide emissions that might be larger than that supported by other evidence.
In recent studies, the “hot models” have even been shown to be ineffective at reproducing past temperatures, a common method used to test their reliability and accuracy. This has cast further doubt on the model democracy approach, whereby all models are given equal weighting when establishing future warming parameters.
(unpaywalled copy here https://www.masterresource.org/uncategorized/climate-models-...)
This is dead wrong. It's a source of wonder in most scientific disciplines that heavily simplified models can have amazingly good predictive power.
Deniers gonna deny. They'll use whatever argument it as hand, including completely nonsensical and contradictory ones, to tarnish, downplay, distort, misrepresent, and fundamentally reject the underlying thing they want to deny.
Simplistic assumptions does not necessarily have favorable outcomes, on the contrary, it's more likely that climate change is worse than what we think it is because of our assumptions. Also climate models are insanely complex, usually contain thousands of equations that sum up the research efforts over the last hundred years, it's not some simple model that one guy can implement in an evening as you are basically trying to simulate the whole earth from the scale of plant stomata and molecular diffusion to the entire boundary layer plus the interactions and feedbacks between the different parts of the earth system.
Could?
This is already happening.
Scientists such as Natalia Shakhova have been studying this for years. This is a video of her from 10 years ago.
The effect is 30% less than previously thought, and global warming is still really really really important.
There is no need to mention previous thought, most people had no previous thoughts.
The title here on HN is the same as the title in the original/linked article. Something I personally live about HN is we don't editorialize by rewriting headlines to reframe things to fit our preferred perception (even when we really believe that perception is correct). This is important for cognitive diversity.
> Methane is naturally destroyed by both chemical and biological processes, including reaction with atmospheric hydroxyl [OH] and chlorine, and by methane-consuming bacteria (methanotrophs) in soil and water. This results in a lifetime in the air of 9.1 ± 0.9 years [12]. Thus, we face an important question—given methane is being removed from the air anyway, why trouble to do this artificially? It may be preferable to dedicate the cost and energy involved in methane removal to the task of stopping methane emissions, which would accomplish the same end result of lessening, halting, or reversing the growth of methane-driven climate warming, or, alternatively, simply to ignore methane and dedicate all efforts to CO2 removal. To answer this question, the specific methods of removing methane must be examined.
Science is hard.
A 30% reduction serves to further show that the priority needs to be CO2 in general, and everything but the low hanging fruit for methane emissions is a distraction.
Of course, the possibility of runaway effects and short term positive feedback loops from methane release from permafrost, etc, is still a concern. I guess a 30% reduction there is somewhat good news.
Sadly, most of the green movement is just Marxism in new clothes and for them the climate change is an opportunity to push their authoritarian and dystopian policies. They use words such as 'oceans boiling' and 'extinction' as a part of their propaganda which are total and utter lies.
The goal for Marxists is to stop human progress and wealth generation. Implementing their policies would result in a way worse world than a world with climate change.
Methane has multiple peaks of absorption
Frankly, we as a global society have FAR more pressing issues than the greenhouse effect, such as:
Collapse of insect and bird populations
Overfishing and plummeting biodiversity as we turn the world into farms and monocultures
Destruction of coral reefs and kelp forests and rainforests
One third of arable land WORLDWIDE is now undergoing desertification
Day zero for many cities as aquifers run dry
Plastic by mass will outnumber fish in the oceans by 2050
Factory farms overuse of antibiotics and superbacteria…
And so on… somehow this “climate change” thing has hijacked the conversation and sucked all the political capital for things like sustainability, switching to non biodegradeable plastics, ending factory farms, etc.
It has a GWP of nearly 100 the first year but falls off rapidly.
If the hypothetical Methane Gun happened, there is immense warming potential that could rapidly melt regional ice sheets.
It is not difficult to see that a reasonable person may ask that if the UN is correct in saying 30% of climate change is due to methane[1] and this paper is correct in saying methane is 30% less effective at warming than we thought, then isn't this whole climate change problem potentially ~9% smaller than we thought? And isn't that actually pretty big? Big enough to potentially have policy implications?
I'm quite sure it's not that simple but nevertheless as a starting point for discovery it's a decent question. It's also a question that will be met with astonishing levels of derision on social media, mainstream media, and in society more generally. Merely asking it will have large international media outlets like the BBC openly describing the questioner as a 'climate sceptic/denier' which, while some may wear it as a badge of honour, actually serves the purpose of shaming them publicly for wrongthink. Social media will of course be far worse in this regard.
We now live in a world where it is popularly considered valid to provide a political (to put it kindly) response to a scientific question. It is, of course, both invalid and indefensible.
I have no ideological aversion to the idea that climate change is real and a serious threat, but the quality of societal discourse on the topic has become so poor and so overtly political that there is absolutely no basis upon which I can accept either of those assertions as _actually scientifically_ true (short of becoming a climate scientist and spending the next however many years personally reviewing all the literature). For me to accept these assertions as fact would be indistinguishable from a declaration of religious faith. It isn't going to happen.
Moreover the conduct of the pro-climate change 'lobby' from the IPCC to the BBC to Just Stop Oil activists has, on the whole, fallen so far short of the standard demanded by the severity of the problem they espouse that I simply don't believe them very much anymore. In my view--and I claim no authority on this matter, this is just how I see it--climate change may well be real and an existential threat, but it may also be a bureaucratic fantasy mistakenly grown from kernels of misunderstood or mistaken truths that has gotten so completely out of control that it's now controlling us. It could also be somewhere in between, or something else entirely: I don't know and I cannot know so long as society keeps excluding valid voices with valid questions.
I suppose I'm a climate sceptic then...but when it comes to deciding between being a sceptic or taking a leap of devotional faith, what choice do I have? Luckily it seems to me the way forward is the same in any case: the pro-climate change people, being the ones comprehensively 'winning' the 'argument' at the moment, need to show a little humility and engage in open debate with the well-meaning sceptics without the ad-hominem attacks, the gaslighting, the censorship, etc. It really is that simple, and the fact it’s so forcefully resisted should, in my view, give us all pause for thought.
[1]: https://www.unep.org/news-and-stories/story/methane-emission...
The article also clarifies that while it is 28x, it also has a second effect in which it traps heat, so in total it seems to get to 20x.
It's generally couched much more cautiously than most of the rhetoric out there.
Its authors seem to really bend over backward to try to accurately characterize the various degrees of acceptance and certainty of the myriad different aspects of the "consensus."
A constant number of cows produce a constant amount of methane which plateaus quickly due to its very small atmospheric half-life.
"Additional methane emission categories such as rice cultivation (RIC), ruminant animal (ANI), North American shale gas extraction (SHA), and tropical wetlands (TRO) have been investigated as potential causes of the resuming methane growth starting from 2007. In agreement with recent studies, we find that a methane increase of 15.4 Tg yr−1 in 2007 and subsequent years, of which __50 % are from RIC (7.68 Tg yr−1), 46 % from SHA (7.15 Tg yr−1), and 4 % from TRO (0.58 Tg yr−1)__, can optimally explain the trend up to 2013." - ["Model simulations of atmospheric methane (1997–2016) and their evaluation using NOAA and AGAGE surface and IAGOS-CARIBIC aircraft observations" (2020)](https://acp.copernicus.org/articles/20/5787/2020/)
"On November 17, 2003 National Oceanic and Atmospheric Administration reported that the concentration of the potent greenhouse gas methane in the atmosphere was leveling off and it appears to have remained at this 1999 level (Figure 1). The Intergovernmental Panel on Climate Change in 2007 acknowledged that methane concentrations have plateaued, with emissions being equivalent to removals. These changes in methane atmospheric dynamics have raised questions about the relative importance of ruminant livestock in global methane accounting and the value of pursuing means of further suppressing methane production from ruminants. At this time there is no relationship between increasing ruminant numbers and changes in atmospheric methane concentrations changes, a break from previously assumed role of ruminants in greenhouse gases (Figure 1)." - ["Belching Ruminants, a minor player in atmospheric methane" (2008)](http://www-naweb.iaea.org/nafa/news/2008-atmospheric-methane...)
«If there was an increase in atmospheric CH4 mixing ratio and the increase was caused by agricultural sources, specifically livestock emissions, the trends in atmospheric CH4 should correspond to dynamics in global livestock populations. *During 1999 to 2006, however, when atmospheric CH4 mixing ratio plateaued, global cattle and buffalo populations* (these species make up 84% of all livestock enteric CH4 emissions; FAOSTAT, 2017) *continued to increase* from 1.46 (1999) to 1.59 (2006) billion head (FAOSTAT, 2017), at a rate of approximately 18.8 million head/yr, *which apparently did not affect atmospheric CH4* over the same period. Since 2006, the rate of increase for the populations of these ruminant species declined to 7.3 million head/yr (FAOSTAT, 2017); we note that FAOSTAT does not specify uncertainty for their estimates, which is likely large for cattle inventories (and emission factors) in developing countries. Thus, it appears that *the global dynamics in large ruminant inventories do not support the suggested farmed livestock origin of the increase in atmospheric CH4* from 2006 to 2015. Potential increases in CH4 emission from non-livestock agricultural sources to the global CH4 budget cannot be excluded. Globally, *the area harvested for paddy rice* (emissions from which are typically 22 to 24% of the emissions from livestock), for example, *had increased 42% from the 1960s to 2015* (FAOSTAT, 2017), although new rice varieties (i.e., water-saving and drought-resistance rice, or WDR; Luo, 2010) require less water and thus emit less CH4 (Sun et al., 2016).»
«As pointed out by Turner et al. (2017), fossil fuel CH4 is not entirely thermogenic in origin (based on its isotopic signature), with *over 20% of the world's natural gas reserves generated by microbial activities (i.e., carrying biogenic isotopic signature)*. Thus, collectively, we can conclude that quantitative attribution of changes in atmospheric CH4 concentrations to CH4 sources based on δ13CH4 data is at least questionable.» - ["Symposium review: Uncertainties in enteric methane inventories, measurement techniques, and prediction models" (2018)](https://www.sciencedirect.com/science/article/pii/S002203021...)
"we find that city-level emissions are 1.4 to 2.6 times larger than reported in commonly used emission inventories and that the landfills contribute 6 to 50% of those emissions" - ["Using satellites to uncover large methane emissions from landfills" (2022)](https://www.science.org/doi/10.1126/sciadv.abn9683)
Right, which is why arguments about going vegan advocate for having fewer cows, which kind of renders the rest of your argument moot.
https://www.researchgate.net/publication/320356605_Agricultu...
"... the concepts of “planetary boundaries” (PBs) and a “safe operating space for humanity” ... are intended to represent Earth system processes, which, if crossed, could generate unacceptable environmental change potentially endangering human existence
The nine PBs currently recognized are the following:
1. Land-system change;
2. Freshwater use;
3. Biogeochemical flows - nitrogen and phosphorous cycles;
4. Biosphere integrity;
5. Climate change;
6. Ocean acidification;
7. Stratospheric ozone depletion;
8. Atmospheric aerosol loading; and
9. Introduction of novel entities.
Of the nine PBs, five are in the high risk or increasing risk zones, with agriculture the major driver of four of them and a significant driver of the remaining one. It is also a significant driver of many of the PBs still in the safe zone.
Reduced meat and dairy consumption is likely to be crucial."
While methane is often cited as the most harmful aspect of animal agriculture, it's only one of many. Let's not forget about increased usage of fertilizers, pesticides, herbicides, and antibiotics, ocean dead zones, as well as the spread of zoonotic diseases. Additionally, animal agriculture can contribute to soil degradation and erosion, damage the water cycle, and lead to droughts and depleted aquifers.
Furthermore, it's essential to recognize that consuming animal products is no longer a necessity but rather a personal choice. This choice not only results in the loss of lives of gentle animals (as only those were chosen for domestication), but it also damages nature and wildlife.
So probably not much.
Nothing will change from the chorus of "well I get all my meat from this local quaint little butcher who knows all the cows by name and they're raised on grassland that cannot sustain arable farming so it's fine, actually", completely ignoring what happens when 8 billion people need to go to that butcher...
Funny, neither can "regular" farmland sustain "arable farming" (or whatever that means). Mainstream food production has a massive input of chemical fertilizers produced from fossil fuels.
The big one is that "if we don't eat cows then all the methane from stuff cows eat won't enter the atmosphere".
One should not forget soil erosion of typical farming, with a big environmental impact. This can be alleviated by letting cows graze on land to stock carbon in the soil (sequestration of soil organic carbon).
