441–450 of 469 posts
What we need is a cryptocurrency that is somehow mined by pulling carbon out of the atmosphere.
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The usual way to increase arable land is by cutting down a forest. "Surely the net biomass stored in fossil fuels could be completely resuscitated, so to speak." - that's a strong no - fossil fuels have accumulated over millions of years, having all that carbon become biomass all at once would not be returning to something that existed earlier but something completely unprecedented, it would require many times more b…
A quick google search suggests there are about 500 trillion pounds of oil left and about 1000 trillion pounds of living biomass. Assuming 5:1 mass:carbon ratio, it shouldn’t more than ~quadruple the total biomass. We could definitely fit that by turning the Sahara into a rainforest or something.
I was surprised that Sahara has been green cyclically.
https://en.wikipedia.org/wiki/Sahara#Desertification_and_pre...
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It does seem unlikely that we'd be able to control temperatures without resorting to sulfur dioxide. It'll probably start a war, but once natural resources start getting scarce I fully expect the affected nation to deploy SO2.
I don’t think you should be downvoted. People really don’t like it because it is clearly not the optimal way to solve the problem, but we should take the possibility seriously instead of down voting anyone who brings it up as something that might happen. We are letting anthropogenic global warming happen because it’s cheaper in the very near term. But climate change is a real thing and will have real, life-threatenin…
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I choose to help people support a portfolio of carbon removal at https://carbonremoved.com If you're working on carbon removal or want to support carbon removal please feel free to email me directly: ewan (at) above website
Great initiative! I offset my emissions with Wren ( https://wren.co – I am not affiliated) and wonder how it compares to Carbon Removed. My current plan there is ~$23 to offset 200% of my emissions for a total of 1.3 tons of CO2/month (if that seems low: I have no car, no commute, live in a 1-bedroom apartment and rarely eat meat). The plans for Carbon Removed are at $15 for 100 kg, $42 for 300 kg, and $65 for 500 kg…
A key difference between us and Wren (and other offset based services) is that we focus on carbon removal - actively undoing a carbon footprint, rather than offsetting it. The way we see it this way: if we emit a ton of CO₂, we should remove a ton resulting in 0 emissions in the atmosphere. If we offset (by paying typically developing countries to change their behaviour), there is still a ton in the atmosphere.
As a result, sequestering carbon dioxide is much harder and expensive. For example, removing via Direct Air Capture is currently around $1000/ton. Via bio-oil is close to $700/ton. At the other end of the scale offsets are typically $32/ton.
I don't want to diminish the efforts of offsets - they have a place and help developing nations transition to more sustainable alternatives - but we want to focus on bringing carbon removal down the curve. To try and make this more affordable we also mix in calculated removals via forestation which is cheaper.
Does that make things a little clearer?
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> Even assuming the forecast 5x increase in "renewables*" I don't know where these figures come from, but the IEA underestimating the deployment of renewable energy, as well as cost reductions, has become a running joke among people who model energy or study the electric grid. Renewable energy is a growing and profitable field, and if you're concerned about not having enough clean electricity to power carbon removal,…
>> Even assuming the forecast 5x increase in "renewables*" > I don't know where these figures come from /../ There is a link to a well respected statistics site right above the line you are quoting, so if you don't know where the figures are coming from, that says a lot.
So, no, it is not clear where these data actually come from, it's not straightforward to find out without paying, and my point, about the IEA being very, very wrong in its projections about renewable energy for more than a decade, still stands.
One solution that I feel is regularly overlooked in these discussions is the establishment of kelp forests. Kelp grows at a far quicker rate than trees, requires no fresh water or land and has the added benefits of restoring marine ecosystems.
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This kind of civil discourse is what makes HN such a gem on the internet.
> discourse Hardly a discourse. Both gents above might have a negligible disagreement but they are sticking firmly to radical green agenda shadow-officially endorsed and promoted by Yahoo Combinator. Also, good for karma income. Just the same for praising comments.
What is this radical green agenda that you identify? I'm not disputing that exists, I'm certainly part of it, and I intend to continue leaning into it. I'm just curious how it looks from the outside.
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I don’t think you should be downvoted. People really don’t like it because it is clearly not the optimal way to solve the problem, but we should take the possibility seriously instead of down voting anyone who brings it up as something that might happen. We are letting anthropogenic global warming happen because it’s cheaper in the very near term. But climate change is a real thing and will have real, life-threatenin…
Because I think you’d be the person to ask: what is the feasibility of putting up a space sunshade to block some incoming solar radiation, using starship/super heavy?
Still sub optimal compared to other solutions but it’s possible we may need to try something like that.
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Because I think you’d be the person to ask: what is the feasibility of putting up a space sunshade to block some incoming solar radiation, using starship/super heavy?
Let’s say you need to reflect 1% of the light reaching the earth’s disc. If you’re using solar sail like devices with an average areal density of 10 g/m² and you have launch cost of $10 per kilogram (using LEO figures because devices made really lightweight can actually move themselves around with pressure from sunlight)… about $150 billion in launch costs. Material/spacecraft costs are a big question mark and can va…
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Where can I learn more about the costs and challenges of thoughtful reforestation, and the key differences between the responsible and irresponsible sort? (Just popping in to ask because it seems like you might know). I'm interested in doing some work in this space but don't have any background.
Hmm… can’t point to one specific book, but there are lots of links. You can google “reforestation monoculture” and “reforestation native species.” This article is a great place to start: https://e360.yale.edu/features/why-green-pledges-will-not-cr... It doesn’t get into the granularity of the costs, but highlights that the basic issue is countries are still hoping to make a profit off these “carbon sinks” by planting…