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To see both the longer trend (graph), a comparison with the value at the same time the previous year, and the current value for CO2, CH4, N2O, and SF6 I occasionally check the Global Monitoring Laboratory (NOAA):
https://gml.noaa.gov/ccgg/trends_ch4/
Link to methane, click on one of the four switched at the top for the others.
Warning: It always is pretty depressing to visit this site.
You can also check out a tab "Growth Rate", for CO2 for example it's https://gml.noaa.gov/ccgg/trends/gr.html -- which is even more depressing. Even the rate(!) increases!
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So, I'm mid-life, and I do what many might say is actually interesting and useful software work, no standard stuff, lots of new things to design and plan and implement in a small software company I co-founded in a team that works well together. Currently we do most of our work for the health sector. Still, I can't take it too seriously. I look at that data and I think to myself, in a few decades we will have problems, many indirectly from more and more troubled nations who will bear the brunt of the climate change, that that silly little piece of software I write seems meaningless if I start thinking about the bigger picture. I'm not demotivated or depressed, it's more the opposite, I can't feel excited about any achievements because I think that most of what we do, what people do these days, is just keeping busy to avoid facing the bigger reality. The show must go on. I've developed the feeling that what we have, even in the rich countries, is much more fragile than people realize.
Unless there is a full stop of digging up any more carbon from below ground, in the form of oil, gas, and coal, and I mean full stop and not just a reduction, the amount of carbon in the above ground carbon cycle is going to keep increasing. No amount of trees planted or most of he other measures proposed will change that. How likely is that to happen?
Your post struck a chord in me. I work with civil engineering (water management) which sounds like it could impact climate change. Nope. I work on how to make our processes more efficient so we can build more infrastructure faster. Infrastructure that has to be maintained CO2 emission free in the future - we are building more of it.
And I am truly bewildered. When I look at all the graphs the only thing I see is that we have to stop everything now. But what I see at work is that we just keep digging with an even faster pace.
This summer I tried to read some old Greek tragedies. The characters have to make difficult choices and it all ends with tragedy despite everyone’s best intensions and efforts. I was saddened by the resemblance on how humanity is tackling climate change. I am afraid we are writing an old Greek tragedy.
On the one hand, capital is flowing into climate tech, and on the other there are several growing communities that are addressing this problem space:
https://workonclimate.org/ https://www.myclimatejourney.co/ https://climateaction.tech/
I volunteer on the first one and am a member on the other two, and there is a relatively good (and growing!) possibility of finding a good match between what you feel and what you end up working on.
There you can find incubators and funds to launch your climate startup or job postings to work on the coolest climate tech companies (and the not so cool ones too!)
I found this interview with former chief scientific advisor for climate change to the UK Government and Oxford professor Sir David King both timely and relevant to your point. He now works at the Centre of Climate Repair at Cambridge.
Here's a related, recent New Yorker article about the melting permafrost.
https://www.newyorker.com/magazine/2022/01/17/the-great-sibe...
> Over thousands of years, the frozen earth swallowed up all manner of organic material, from tree stumps to woolly mammoths. As the permafrost thaws, microbes in the soil awaken and begin to feast on the defrosting biomass. It’s a funky, organic process, akin to unplugging your freezer and leaving the door open, only to return a day later to see that the chicken breasts in the back have begun to rot. In the case of permafrost, this microbial digestion releases a constant belch of carbon dioxide and methane. Scientific models suggest that the permafrost contains one and a half trillion tons of carbon, twice as much as is currently held in Earth’s atmosphere.
But doesn't the article suggest that the recent rapid rise comes from methane produced by microbes? If this is true, it is not the melting permafrost, but (intensive) agriculture that is the culprit.
> But since 2007, when methane levels began to rise more rapidly again, the proportion of methane containing 13C began to fall (see ‘The rise and fall of methane’). Some researchers believe that this suggests that much of the increase in the past 15 years might be due to bacterial sources, rather than the extraction of fossil fuels.
So then what happens, the microbes eat stuff, more soil is produced, more trees and animals grow, more rain comes, more stuff gets buried, and the cycle repeats itself?
Honest question, not refuting anything here just a lot of the articles stop at the melting part, what happens after that?
Climate Scientist, Ilissa Ocko[1], talked about Methane and Climate Change last month at a TED Talk. The video is worth watching - https://www.youtube.com/watch?v=tlWuP7wESZw
BTW she works for the Environmental Defense Fund who will soon be launching a satellite to measure methane (funded by a $100MM grant from Bezos). Despite giving a TED talk she's a serious scientist.
Genuinely curious - while Methane is a far more potent greenhouse gas, isn’t its half life in the atmosphere only 9 years? Wouldn’t this make it far less concerning than CO2 with its half life of 120 years?
Looking for serious answers.
Methane is CH4. It decays to CO2 + 2 H2O.
So as long as it’s methane it’s hundreds of times worse than CO2, then it becomes the same as co2[0]. Never better.
Which is why despite a short half life it has a global warming potential of ~25 over 100 years (Co2 is 1).
Then you also have the issue that even if it’s short (relatively, it takes multiples of the half-life to really taper off) for that duration your GW effect really shoots up, which tends not to be a good thing, 120 years is already quite short for biological systems to adapt, 10 is basically infeasible.
[0] actually a bit worse still as 1t ch4 yields 2.7t co2 and gwp is mass-relative
I think you're spot on in your observation. Reducing methane would help and definitely has its place, but CO₂ is a totally different beast. CO₂ is best thought of as a "stock pollutant" meaning that the more you have of it, the worse the effects. This follows directly from that fact that CO₂ sticks around in the atmosphere for millennia, increasing atmospheric radiative forcing. Methane, on the other hand, is better framed as a "flow pollutant" - it's harm is ~proportional to the rate of emission. This is a direct consequence of its much shorter atmospheric lifetime.
Here's a useful twitter thread from a real expert: https://twitter.com/hausfath/status/1425572803508465664
And if you're up for a pretty technical (but still fairly approachable) read, check out R.T. Pierrehumbert ''Short-Lived Climate Pollution.'' Annual Review of Earth and Planetary Sciences 2014 42:1, 341-379 [https://doi.org/10.1146/annurev-earth-060313-054843]. Near the end of the paper, he delivers this gem: "Methane mitigation is like trying to stockpile bananas to eat during retirement. Given the short lifetime of bananas, it makes little sense to begin saving them until your retirement date is quite near."
Carbon emissions are correlated to human activity. We can dial them up or down theoretically through human action.
Methane emission through permafrost (both land and submarine) could end up as a cascading natural emission that forms a feedback loop.
I think that's a big part of why people are panicking.
A couple things.
First is that we are on track to overshoot the goal of limiting warming to 1.5C. It's now more a question of how much we are going to blow past 1.5C. Every bit counts now and a pulse of very potent greenhouse gasses at this time is very unhelpful.
2. There could be tipping points that aren't predictable. Methane may temporarily add a small increase to the global average temps, but could end up being the difference for whether permafrost melt begins releasing large amounts of co2 and even more methane that take us up to some even higher temperatire equilibrium.
Global warming is a massive unplanned, uncontrolled experiment with the thermal and chemical properties of the only biosphere we know of. The sooner we stop that experiment the safer humanity will be overall.
Methane has ~25 times the global warming effect as an equivalent amount of carbon dioxide.
Source: https://www.epa.gov/ghgemissions/understanding-global-warmin...
> Wouldn’t this make it far less concerning than CO2 with its half life of 120 years?
In the pre-industrial era the oceans outgassed CO2 to the atmosphere to prevent land plants from suffocating themselves by sequestering all the carbon dioxide. In the post-industrial era the oceans capture a significant percentage of the CO2 that humans generate (because CO2 is heavier than air, and easily dissolves in water).
The most important considerations for the earth's atmospheric heat balance are the heat inputs from the sun (solar cycle) and underwater volcanoes, and the shielding provided by volcanic eruptions. The oceans store heat during the summer, and release heat during the winter.
My previous comments: https://news.ycombinator.com/item?id=20002823 / https://news.ycombinator.com/item?id=20013166
I hadn't thought of carbon emissions in terms of half lives before. I thought that carbon emissions (presumably from fossil fuels) were more of a permanent change.
The carbon used to be deep underground, and now it's in the atmosphere. Where does half of it go? I know that it ends up as part of a photosynthetic organism, but then later that plant decays and its back in the atmosphere again, right?
And given a changing climate, can we rely on the atmosphere->plant rate remaining constant for enough for our ideas about the half lives of various greenhouse gasses to remain relevant?
The concern is faster warming and an out of control positive feedback loop.
While Methane has a shorter half-life it is also a much more effective GHG. The common way to look at this is Global Warming Potential, which is measure in CO2 equivalents. You can find this on the wikipedia: https://en.wikipedia.org/wiki/Global_warming_potential
Notice that you can look at the GWP potential over time spans. For methane, over the next 100 years (which is the period that will impact most HNers the most) it is at least 20x as impactful as CO2.
The reason this matters is because the biggest unknown with climate change is positive feed backs. A classic example of this is that as the arctic has less ice it also reduces the albedo of the oceans allowing them to absorb even more heat faster.
Another, methane related, theoretical, positive feed back is methane clathrates which are essentially frozen stores of methane deep in the arctic ocean. If the ocean were to warm up enough this might rapidly release methane leading to a catastrophic runaway warming scenario, leading to what is suspected to have caused rapid climate change in the Quanternary period [1].
It is currently believed by many researchers that, in the specific case of the 'clathrate gun' firing, it is unlikely to happen. The trouble is we don't know for sure. That is just one unknown, potentially devastating positive feed back.
If you read Peter Ward's work (and some others as well) it looks like at various times in the history of the planet there was very rapid, very destructive climate change that was caused by a cascading series of positive feed backs. We don't know exactly where these are, but the more methane we release (and CO2) and the faster the planet warms the more likely we are to find these.
It is important to note also, that these positive feedbacks are not factored into the IPCC report (just like the potential collapse of Thwaites Glacier is not) because the is no way to effectively model this and make predictions about them. It means that if you think the IPCC report sounds bad (or even if you don't) there is a lot of potential risk not mentioned in the various pathways there.
Depends on how much methane ends up in the atmosphere. A lot of methane released in a short time, could end up having very dramatic effects. For example, Siberian permafrost melting and releasing a lot of methane would probably have some measurable and dramatic, but short term effects. However, the addition of a couple of giga tons of methane released per year is not going to help slow that melting process down. If that's a process that lasts a few decades/centuries, it would raise methane levels more or less permanently throughout that period. It would recover once methane release stops/slows down.
We'd be looking at a very different planet by then with higher see levels, higher temperatures, and a lot less ice on Greenland, Antartica, and most mountains. You can haggle about just how bad things would get in terms of temperature rises, and sea level rises. But lets just say it wouldn't be very good. It would recover eventually. But the problem is that that recovery process is going to take thousands of years.
the answer, or part of it, lies with methane clathrate [0]
> a large amount of methane is trapped within a crystal structure of water, forming a solid similar to ice. Originally thought to occur only in the outer regions of the Solar System, where temperatures are low and water ice is common, significant deposits of methane clathrate have been found under sediments on the ocean floors of the Earth.
deposits of solid methane ice can exist trapped on the seafloor [1]. this is possible only at the extreme pressures of the seafloor [2].
so, on its own, a little methane in the atmosphere is not a big deal, because of the short half-life.
except, you have methane ice deposits in the ocean that can melt if the oceans get a little bit warmer.
this can enter into a fun little runaway feedback loop pretty quickly. little bit of methane melts, causing a little bit more ocean warming, causing more methane to melt, etc.
if this feedback loop were to occur, the evidence you would expect to see would be spontaneous release of methane emissions from the ocean, and you would expect it to be happening in places where the warming ocean put methane clathrates right at their melting point for that depth & pressure of seawater. which...is exactly what's happening [3]
> The study, to appear in the journal Geochemistry, Geophysics, Geosystems, a journal of the American Geophysical Union, shows that of 168 bubble plumes observed within the past decade, a disproportionate number were seen at a critical depth for the stability of methane hydrates.
> "We see an unusually high number of bubble plumes at the depth where methane hydrate would decompose if seawater has warmed," said lead author H. Paul Johnson, a UW professor of oceanography. "So it is not likely to be just emitted from the sediments; this appears to be coming from the decomposition of methane that has been frozen for thousands of years."
a similar feedback loop is possible in the Arctic tundra [4], where permafrost can melt and release trapped bubbles of gases that include methane, which in turn will warm the planet a bit and cause more permafrost to melt.
and of course the two feedback loops are able to reinforce each other, because a bit of methane released from the arctic also helps heat the oceans, and a bit of methane released by the oceans also helps melt the permafrost.
0: https://en.wikipedia.org/wiki/Methane_clathrate
1: https://en.wikipedia.org/wiki/Methane_clathrate#/media/File:...
2: https://en.wikipedia.org/wiki/File:Methane_Hydrate_phase_dia...
3: https://www.ocean.washington.edu/story/Bubble_plumes_suggest...
Note: I work at a startup working on removing methane from the atmosphere.
Responding to several comments: yes, we need to get rid of the excess CO2. In fact when CH4 is broken down (mostly via hydroxyl† or, over oceans, Cl reactions) you end up with CO2 anyway.
So, as you ask, why worry about CH4?
The radiative forcing function of CH4 is, depending on your baseline, 30-80X‡ worse than C02. The rise in methane levels from 750 ppbv to 1900 ppbv is believed to have raised the temperature by as much as 0.5 C. So eliminating it buys more time to work on other problems.
The second problem is you can't really eliminate* emissions -- they come from diverse sources, almost all of them natural. You can see this in that the 750 ppbv level that was reasonably flat before the widespread adoption of the steam engine (around 1775 when Watt and Boulton got their patent)** -- emission and oxidation/removal were roughly balanced. Another way to look at it is that 1900 ppbv today was all emitted over the last decade, whether "naturally" or not.
I put "naturally" in quotation marks because yes, some would be emitted anyway without humans, but most of the emissions that come from humans are from biological activity that would not otherwise have occurred: primarily agriculture, but also fossil fuel extraction. If we somehow stopped all the latter it would cut anthropogenic emission by perhaps a third; livestock maybe the same amount, or maybe half in aggregate. But you aren't going to stop growing crops or dumping stuff in landfill.
And many of these sources are quite diffuse; oilfields result in lots of seepage, and who can fit a catalytic converter to a swamp?
And of course methane bursts from melting tundra heating continental shelves and the like -- not sure anybody has an idea how much of that there is. You can see craters from these bursts if you walk around in the arctic. And as the article mentions, it's not just the frozen methane, but as the frozen tundra melts decomposition accelerates. One can imagine a significantly large offshore burst that could wipe out agriculture for a few years -- probably a bad thing if you are a fan of vertebrates.
If you want to know what human activity bugs me the most, its not livestock, it's a transition to natural gas (methane, basically) as a "greener" fuel for transport, heating and electricity generation. More gas means more leaks and emissions and further cooking of the planet. And when those ships have been launched and power plants built they'll be in operation for decades because of that's how long they'll take to depreciate. The EU has come out in favor of this; the IMO is encouraging shipping to make the transition, and of course some countries depend on its export.
PS: everyone makes cow fart jokes but a point of trivia: it's actually cow burps as the cow is a ruminant.
† For unknown reasons OH levels last year seem to have dropped. Eek!
‡ These calculations are arcane, depending on what parameters you're trying to compare. We just use 30X in the company.
* There are various projects to eradicate point sources: barns, landfills, some old mines. We need more of that too.
** OK, obviously some coal was burnt before the Boulton and Watt engine and adoption was not instantaneous but you can see the bend right around the end of the 18th century.
Edit: add the point about gas being considered a "green" fuel.
This is pretty interesting/terrifying. Could you say more about the startup? At least its name?
Speaking of diffuse, how do you sequester something that is at super low concentrations like atmospheric methane?
As an analogy, my home reverse osmosis filter doesn't even come close to touching things that are in the parts per billion.
Also, it isn't as if atmospheric methane is evenly distributed across the globe [0]. How do you expect to collect methane across borders?
What is the startup removing Methane? (sorry if I missed it in your profile)
Based on the past two years, good luck with that.
Wonder how much damage the billions of gallons of off gassing is costing the country and world from the Bakken fracking fields (North Dakota, eastern Montana)
https://www.smithsonianmag.com/smart-news/at-night-giant-fie...
It seems more like this is the "clathrate gun" hypothesis coming to fruition.
Thete was a related article recently about leaky pipes that leak methane in extraordinary amounts.
Uh oh, time to prepare to spray sulphur particles to upper atmosphere?
To add to this a bit: if increased atmospheric heat is _causing_ the release of greenhouse gases, then directly reducing the temperature of the atmosphere might be the only way to slow down that release. Secondly, since there is a positive feedback loop here, the earlier and more decisively we act to directly reduce the temperature, the less such geoengineering we will need to do. Right now we only need to counteract X parts per million of methane in the atmosphere, but in the future we would need to counteract X+Y parts per million, necessitating a bigger geoengineering response.
Many humans. Rich life (individual freedoms and high material quality of life). Low environmental impact. Pick two.
EDIT: this apparently is one of my most disliked comments. To clarify, my point is that we can’t have both unlimited population growth and a high quality of life without accepting environmental impacts. If a high population of people have to crowd into dense micro apartments and give up cars and face constant bans on things they like, then their environmental footprint may reduce but their quality of life will go down. On the other hand if population controls were instituted, then a high quality of life could be possible with a sustainable level of environmental impact.
> Many humans. Rich life (individual freedoms and high material quality of life). Low environmental impact. Pick two.
I really don't buy this, it seems illogical to me.
We have technologies that can produce a rich and comfortable life with much less or zero emissions, nuclear, renewables. We don't need to fuck stuff up as bad as we have. We've fucked stuff up this bad because of lobbying, resources companies have lobbied and fought long and hard to keep selling this poison to the world. To keep us buying cars that use petroleum. To keep people believing that it's either oil and coal or you're going back to the stone age it's bull shit because oil and coal is the stone age.
If you buy into those technologies I've mentioned above, you don't really have to entirely give up the life you know, in fact you might get to keep the life you love and have cleaner, better air to breathe.
We've woken up, but we still have those cretins doing their dirty work (the Australian Government for example.
We've woken up but it might be too late now.
Tell China.