To your sequestration comment.

No one is saying don't plant trees. Fuck yeah, plant all the trees! But that won't wont be enough. Sequestration will get better, but one of the big things it helps with is locality. CO2 isn't homogenously spread across the globe. It also doesn't spread very well. Concentrations vary drastically over the year and so do plants' ability to capture carbon. Carbon can build up in certain regions. Worse, it can pool where we can't grow trees [0]. Places where we can't get enough water to introduce new populations of trees (without significant carbon costs, defeating the purpose. Also the local ecosystem) Cities. The Arctic. The ocean. I'm all for planting trees (even beyond CO2, I just feel better around trees) but people need to stop making the trees vs sequestration argument. It's trees + sequestration (air and ocean) + promoting corral development + more. (This same argument applies to a lot of things, especially in climate. It's not a "this vs that" argument, it's "this PLUS that".

[0] https://youtu.be/x1SgmFa0r04

Sequestration is also good for catching carbon at potential emission sources; it's easier to grab CO2 out of the atmosphere at the point where you're burning methane than to let it out in the atmosphere and then try to catch it again.

(Or, in some interesting experiments, even before emission; there's work on splitting methane from natural gas into carbon and hydrogen and just burning the hydrogen. Gets you something like 66% of the energy of burning the methane completely, and with no CO2 emissions.)

Re: your second point, splitting methane into H2 and CO2 is not something that's being investigated at lab scale, it's how 95% of global hydrogen production today is done. We're talking close to a trillion cubic meters per year from steam methane reforming.

It's just that most of the time, resulting CO2 is just released instead of being stored. But that is changing, fast.

I was specifically referring to pyrolysis, where unlike steam reforming no oxygen is introduced and so the carbon comes out as solid graphite. Scaling the process, and running it in a continuous-operation reactor, is still an area of active engineering work (see e.g. https://pdfs.semanticscholar.org/d36a/ff0a2db0f99a92c2debd5b...), mostly focused on designing the physical system so that the solid carbon comes out nicely during the reaction instead of gunking up the works.

What are the benefits of pyrolysis versus steam methane reforming (SMR)? My immediate thought would be that you leave energy on the table, and that storage at scale is harder when the end result is graphite. Moreover, SMR is proven technology at very large scale.

One advantage is that it produces high-purity graphite, which is a moderately expensive commodity, used for electronics manufacturing (especially power components in batteries), structural carbon composites, and machine lubricants.

The percentage of carbon captured is also damn near 100% - quite a bit better than gaseous carbon capture techniques I've heard of.

You do leave quite a lot of energy on the table (losing somewhere between 30% and 50%), so this is a technology that is only economically viable with high emissions pricing. But that seems like the way Europe is going anyway.

And yes, SMR is the proven and clearly superior technology right now; I'd call this TRL 4/5 right now. But with another decade of development?

Aha, so it's targeting "CCU". Then OK, I can maybe see there is a point initially, but not at anything near the scale we need.

Global graphite production from mining is at 1 megatonne/year, while synthetic is a few hundred kilotonnes/year. We need CCS to operate at tens of gigatonnes per year, that's four orders of magnitude beyond all the graphite the world needs.

This is the problem with anything CCU - there just aren't viable options with consumption at the gigatonne scale.

I'd imagine extra graphite is pretty easy to store, though?

At the gigatonne scale, nothing is easy to store. Fill the entire Hoover dam with graphite, and you've stored 6 gigatonnes. We need to store tens of gigatonnes per year for a hundred years.

We could put it down in empty mine shafts... or build entire mountain tops out of it!

That’s a cool video. However the variation looks to be only about 2% from highest to lowest.

Trees will actually do the trick. I looked for an international business that would plant a 1000 trees for me which would offset my entire carbon footprint for my entire life. Didn't find anything except a local one in Iceland [1] in Icelandic only (good luck with Google Translate).

I can offset my footprint for 800$/year and I think it's going to be my New Years resolution. No more carbon from me.

Finding land and planning trees for it should be a global business. There are a lot of people like me with disposable income that would invest in something like that.

[1] https://kolvidur.is

Please also include a resolution to reduce your carbon emissions.

Remember that planting trees only work if you have the guarantee that in the future these trees will not be burned. Also, some natural decomposition also emits CO2

Planting trees can delay/slow down climate change. What happens in a decade when planting trees does not scale anymore and we've kept increasing our emissions in the same time?

I am about 50 years old. Planting trees scales for at least 50 years. Something on the order of 1000 trees will offset the entire footprint of a upper-middle class non-jetsetter (eats meat, travels 2-4 times per year, car, modest house).

There are a lot of technology promises on the horizon that will hopefully solve the next inflection point, but that's not my climate crisis, it will be the next generation. Hopefully by then the human race will have developed fusion or other energy technologies.

I’m no biologist but coral seems incredibly f*ed whenever I hear about it. Is there any chance of us actually saving coral?

There's a crash plan to save species of dying coral and another plan to develop/disperse heat-/acid-resistant species.

Next time, could you get a video from someone who's actually seen a tree?

That video was just awful. It's only redeeming feature was that it was short. Here's what he got wrong:

1. The mass of CO2 in the atmosphere is about 3E+12 tonnes (not tons). Around a third of that is additional from humans, so around 1E+12 (cf trillionthton.org - they were a bit optimistic). That's pretty close to what he had, only out by a factor of 2, but purely by chance (there's a fair bit of that).

2. He rounded down the population, so the figure of 130 tonnes per person is again, pretty close.

3. The 0.33 tonnes per year from just breathing is beyond stupid. Unless you're drinking gasoline and eating coal, then all the CO2 you breathe out came from the atmosphere in the first place. It came from growing plants. This is just lazy and ignorant. It's not like he even uses this figure anyway.

4. Typical per-capita CO2 is not "10-ish tonnes per year" for a developed country. That's the high end. The UK is hardly a shining beacon of green policy, and even it is at 6.5 tonnes per year. What's more, we're trying to improve on that. 5 tonnes per year is closer to what the average person can easily manage without sacrificing anything.

5. Not all CO2 emissions stay in the atmosphere. A large part are absorbed by the oceans (hence ocean acidification). He should know this.

6. Great, now we've got the bizarre rectangular tree. Was the volume of a cylinder too much work to look up? Anyway, it's actually oddly difficult to get the total mass of a tree (not that he tried), because lumber yards tend to only care about the trunk. I found a site that gave a complete measurement of an oak, including canopy and roots. It came out to around 20 tons, around 10 tons dry biomass, giving around 5 tonnes carbon.

7. Carbon. Not CO2. Multiply by 44/12 to get the CO2 required. That's 18 tonnes CO2 per tree. Let's drop that down to 10 and say we have small trees.

8. Wait, what? He didn't even use the volume. He just guessed 1 tonne C02 per tree!

9. When trees die, they leave a gap in the forest and new trees grow. How else would forests last for thousands of years? Once you've planted the trees they will replace themselves. What's more, the wood could be used for building or furniture which means it will retain the CO2 even longer. What's even more, giving ourselves a hundred years or so breathing space while we reduce and reverse emmissions is absolutely worth it.

Huh, I didn't mean to type so much but there was so much wrong with that video that I just kept going.

With you until the last point. When newly planted forests mature, a lost tree is not generally replaced. Trees around the 'gap' grow into the gap and take the sunlight, getting larger in the process.

In this way a stand of small trees becomes a much-less-dense stand of very large mature trees.

Don't know how it affects the analysis - is a mature forest more carbon-dense than a newly-planted one?

Yeah, I did oversimplify that. I guess I was really saying, that if your trees live for 100 years, say, it's not like the whole forest disappears once the 100 years are up.

And, of course, if it's used for forestry, the trees will be continually removed and new ones planted.

Nearly every day on here there's a thread about empty/meaningless work and feeling like we're not contributing anything that will matter 50 years from now - and I often participate as I feel this way quite strongly. This is the kind of work that's meaningful. This is a huge commitment to well-thought-out climate healing and using wealth for actual tangible good. Stripe already deserves a place above FAANG for their incredible work culture [1] but this goes even beyond that and would be fantastic to contribute towards. I'll be checking their careers page often, in case they get into hardware.

[1] https://news.ycombinator.com/item?id=19422833

The founders of Project Wren (https://projectwren.com/) went from building HR Software to building software to combat climate change.

We need profitable enterprises focused on this large global problem! I think the tides are starting to shift and would love to see the smartest minds of our generation focused on this issue!

You know, I would love for an option that just asked how old you are and just let you pay to offset your expected life's worth of tree replanting (this might just be the closest thing I've ever seen).

That's quite a hard figure to come up with I'd think, though there's no problem with overshooting of course.

My personal emissions going forward are likely to be way lower than previous years simply due to awareness.

The big polluters, like airlines, energy, transportation, and chemical companies are the ones that will have to take these steps to see any effect. Every bit helps, of course, but the cost of implementing something like this is doable for some, while for many would mean extinction, or fundamental changes to their business model.

I think we need to implement world-wide tax on pollution to avoid some crazy externalitiees.

For example, cheap flights used frequently are a ridiculous luxury we cannot afford. I know lots of people that use budget airlines more than once per month to make weekend trips across Europe.

The amount of CO2 they are putting into the atmosphere is simply insane. A bit more than doing the same trip by car, for each passenger.

A carbon tax is well known to be the rational solution to the problem. Even conservatives agree.

It just happens to be politically impossible.

People pretend it's hard to create a carbon tax, but it's really not. Just tax the fuel (gas/oil/coal), and the cost will be passed on to polluters.

Edit, of course, politically yes it's hard.

Does it have to be?

Planet Money had an episode about "revenue-neutral carbon tax", where all the money collected is returned back to the tax payers, to spend however they want.

The point of this tax is not to raise money, but to change behavior. This, a family that drives to work and school every day will pay more carbon tax, but this will be offset by the tax refund (or lower income tax). And a family that finds ways to reduce their carbon footprint will benefit from the tax refund and able to spend it on other things.

WA state had a carbon tax initiative but the revenues went to environmental efforts, and it failed. I think if it were made revenue-neutral, or heck, even made as an overall tax-cut to please the fiscal conservatives, I think it would pass (although it would face pushback from environmentally minded about not doing enough).

Here is the Carbon Fee and Dividend proposal: https://citizensclimatelobby.org/carbon-fee-and-dividend/

I like it a lot, but the problem is the major industries that will be heavily impacted/closed down as a result. They have immense political power, and I don't see any way around that. Hope I'm wrong.

And that's of course just one country out of 200. There is no local solution to global warming!

They tried that here in Canada, and it is both too small to have much impact, and getting massive pushback from the Conservative party.

You have to keep in mind that even if it’s revenue neutral, explaining the scheme to taxpayers is going to be difficult, and your opponents are going to try their darndest to make it sound unappealing, even if it means spreading misinformation.

The trouble is “polluters” is everyone in society. People who use a lot of carbon feel personally attacked bu such a tax...because itmis in fact directly affecting them.

A carbon tax is my top priority. There’s no sense denying the opposition though. The yellow vest protests in france were from a fuel tax.

Are electric airplanes feasible in the foreseeable future?

Foreseeable future, yes. Short term future (<15 years)? I wouldn't hold my breath. Might happen, but probably not.

No. That's physically not efficient. Synthetic fuels may be, though.

We already know we can produce jet fuel from captured CO2 from the air. The trick is making it cheaper, particularly energy-wise. We can't dedicate half the world for solar panels to make fuel.

> The trick is making it cheaper

Honestly, this is a problem with a lot of technologies. Especially in the green sector. That doesn't mean we shouldn't keep funding research into it and trying to make it cheaper, but also a reason to be cautious.

I think it’s on all of us, including all the corporations. We should have a carbon tax to disincentivize mass c02 production - at the moment all the profits are private and all the losses (to the environment) are public. If they want to pay someone who’s planting trees for carbon caps then that’s fine for me. Just solve the damn problem. Who’s standing in the way? Shareholders of the above companies (and by proxy, the lobbyists and politicians). Because protective action doesn’t get them gains. It requires government action.

It is difficult to get people to agree if it means gas and cheeseburgers cost twice as much.

It's literally economics 101: externalities, but for some crazy reason in the US it's seen as a leftist anti-capitalist issue.

Because you are acting like this would punish the company. It might to an extent but in reality consumers would hurt the most. That in my opinion is why it doesn't happen.

Not as much when the carbon tax is tax-neutral. In Canada we started getting back a carbon tax credit. Consumer impact is still there but a lot more mitigated.

It’s meant to ‘punish’ consumers: it needs to be painful enough that consumers reduce their consumption, otherwise pollution will not be reduced.

Right but it's not going to punish consumers equally. It will hurt the poor a lot more than the rich imho. Essentially a regressive tax moving the burden for the climate change problem to the poor.

The tyranny of the majority :/

Because reducing US emissions to 0 will have no effect on global warming.

Reducing emissions by 14% will have no impact? I doubt that very much.

And that's just direct emissions; the emissions of other countries can often be attributed to supplying to the US.

Individuals matter too!

Netflix made had $5.8B in revenue from small $10-20 subscription users!

Today, for $20 a month you can offset your own carbon footprint! This matters because the more resources that goes into fighting climate change allows innovation. Even by generating more demand for carbon credits and offsetting, new businesses can thrive and grow by fighting climate change!

I've been super obsessed with https://projectwren.com (YC S19) for these exact reason!

It’s a great project but they could be more clear about that 20% cut they take and why it’s double what they partners take. How does it scale? 20% makes sense when you are dealing with, say, 100m of donations, but not so great when it’s 1B. At 1B they’d be taking 200m for what? Hiring the best talent in the world, to do what exactly? I don’t know, I wish them well and hopefully they get more clear about their cut and lower that over time. I think if you are really going to make an impact you must be targeting few billions of donations and 20% is just unreasonable.

I like it, but why do I have to give my email for emission calculation? It's off-putting, I don't want even more spam. And I will tell them where do I live and how, will they package it with my email and sell it to ad companies as a handy profile?

Sorry to be paranoid, but most startups (uber, airbnb, paypal, not to mention facebook ...) are evil and exploitative.

Wren co-founder here — we ask for your email so we can send you a report on your footprint (if you choose) or come back to the onboarding flow later. We're spinning the calculator out into an open resource soon though!

Finally, we just started two months ago and have not sold user information to ad companies nor do we ever plan to. That sounds like an evil and unnecessary way to go about not accomplishing our mission.

Just got my first report from Project Wren! Loved it so much I copied and pasted it here so I can share it:

https://www.notion.so/chrislu/Project-Wren-August-17th-Updat...

Way less than $20 a month in a lot of the world too. Americans have a footprint twice as high as Brits, even.

Cars and air-con are the main offenders there, right?

And air travel

I get where you are coming from, but should we really tolerate fundamental changes to our planet over fundamental changes to a business model?

Here is a whole (open access) journal issue on negative emission technologies: https://iopscience.iop.org/journal/1748-9326/page/Negative%2...

Short summary: There is no free lunch. Almost everything is expensive, natural systems (afforestation and land use change) are cheaper but more variable. The cheapest negative emission technology is not to emit in the first place.

I've actually been slightly interested in buying some cheap land outside of town and slowly planting trees to forest it over the next decade. The goal would be to plant enough trees to cover the carbon footprint of me and my entire family.

What I don't know is where I can find out which trees are particularly suited for carbon capture. From what I've read, fast growing trees will capture carbon quickly, but only if you harvest them, prevent rotting of the wood, and replanting a new crop.

Slow growth trees will store more carbon, but it takes a longer time for it to accomplish it.

I suppose it's like one of those "Good, Fast, Cheap - Pick two" situations. Is it better to capture a lot of carbon quickly to help the planet ASAP, or to kick-off the planting of trees that will capture carbon for the next 300 years?

Even when that's decided, how do I pick which trees aren't just suited for my area (relatively easily with native tree guides), but also well-suited for carbon capture and survival in an increasingly chaotic climate and ecosystem?

Recent paper on tree planting potential: https://science.sciencemag.org/content/365/6448/76

Don’t you then need to worry about enforcement mechanisms to keep those trees from getting cut down? If they’re all harvested after say n decades, there’s no net effect on climate.

Forests have evolved into recycling ecosystems. When a tree dies naturally, it gets decomposed by various fungi and other organisms which, over time, release the stored CO2 back into the atmosphere. So the CO2 is released one way or another. What matters is that the living tree stores CO2 in its wood. Cutting and replanting might even increase the amount of stored CO2 because any wood that's used in the building industry is wood that doesn't decompose for decades to come. Wood you cut down to burn right thereafter probably reduces the storage capacity, but it's not zero due to the living trees!

Forests used to be real carbon sinks meaning that trees would just die without decomposing, because life hasn't figured out yet how to decompose it. This is how coal was formed around the globe.

Maybe some better technology to sequester CO2 emerges. But planting trees is a good approach for the start. If we want to slow down climate change, the CO2 sequestration industry will have to become huge within the next decades.

Burying biochar (the superset of charcoal, basically) in old coal mines or other geological structures is a feasible way for long-term storage. The carbon content can be up to 90%, depending on the method. Biochar can be made from nearly all forms of biomass as long as it's dry enought.

Now I wonder how would old coal miners feel if you told them nowadays the coal is supposed to go in the ground.

I think, they would be happy to keep their jobs and get paid for several decades to come. Also, the coal companies wouldn't have to write off their investments, since some of their technology could probably be reused.

How does it follow that there's no net effect on climate (or amount of atmospheric carbon) if the tree is cut down? I can only see that if the timber is burned for fuel. If someone instead carved the timber up into N skateboards, modulo waste, the carbon would stay with the skateboards.

Skateboards don't stay skateboards forever. Eventually they'll be thrown out, where they'll degrade & eventually decompose, re-releasing the stored CO2.

True, but my model of CO2 is that its damage is proportional to the area under the curve (quanity CO2 * time in atmosphere). So deferring that C02 release by 10 years is strictly a win, b/c you haven't incurred the climate effects of that C02 for those 10 years.

Mostly into the ground, no? Isn't that how petroleum was formed in the first place?

It depends entirely on where the skateboards and other wood-derived waste ends up. If it's not properly disposed of (e.g. litter), then it will release most/all of it into the atmosphere. If it's incinerated, it's all released. If it's in a landfill, it depends on whether and how effectively the landfill is sealed.

Probably not. Most of the oil we find comes from a period when very few organisms could break down waste from dead trees and plants.

Even if the trees are burned for fuel, that may offset some amount of burning fossil fuel and so be a net win.

If you cover an area with trees that is today not covered with trees, that area will absorb CO2 from the atomsphere.

Even if the trees die or are cut down, as long as new ones are allowed to grow, that area will absorb roughly constant amount of CO2.

Now, if we can harvest some trees regularly, and use them to replace plastics or fossil fuels, then that's a win for the environment even if those harvested trees end up releasing their CO2 back to the atmosphere, because we didn't introduce any _more_ CO2, we just recycled what we already have.

What? You want them cut down and used in carbon storing areas, like construction. Trees capture way more carbon while growing, so ideally you cut them down and replant them.

How long do you think this climate crisis will last?

If you think it will be over, or at least completely unrecognizable, in 50 years your - in itself valid - concern doesn't matter.

If I imagine people 50 or 100 years ago trying to plan to solve our problems in 2019, knowing what they did then, I don't think they could have accomplished much of anything of substance, even with the best intentions and the commitment of huge resources.

When a tree grows, it captures carbon. If after N years it is cut, in most cases that carbon is NOT going to go back to the atmosphere. Most CO2 emissions come from fossil fuels (oil, etc), NOT from voluntary wood burning.

Wood burning is not the only way to release that CO2 back into the atmosphere. Just cutting a tree and letting it decompose also releases the same carbon. You need to store it in wood form, or bury it deep.

Google should also do this as zero emissions aligns with "do no evil".

Note that you do not have to wait for Google: You can just start searching using Ecosia (https://www.ecosia.org/) which use their revenue to plant trees around the world and are also a "negative emissions" operation. (Yes, the results are not as good as Google's, but for me they are good enough in the vast majority of searches, and for the remaining I can still hop over to Google.)

They should add a button "Try this search on Google instead" at the bottom of the first page, then I would probably try them. Otherwise it's too much of a hassle, especially on mobile, tbh.

You can add "#g" to any search and it will directly redirect to Google (similar to DuckDuckGo's shebangs). This works very well on Desktop, but I agree that it's a bit of a hassle on mobile...

Am I mistaken in thinking that afforestation is technically a carbon sequestration strategy?

No, you are not. Trees naturally capture carbon in the form of wood. I noticed that distinction too in the post and assume they meant "modern" carbon sequestration engineered by humans.

There's also a big middle ground. For example, some semi-green power is generated by breaking wood into flammable gases + carbon ("biochar"), then burying the carbon and burning the gases.