2 HN users recommended this talk1 month2019–2022score 1.5
Years with an HN recommendation, 2007–2026
HN commenters call it a fantastic talk and cite it in climate threads for the carbon debt framing and tree-planting cost estimates.
Tom Chi gives the opening talk of a Foresight Institute competition on clean energy and clean air, framing excess CO2 as a carbon debt to repay and discussing large-scale tree planting, including by drone.
Related: GoogleX co-founder Tom Chi gave a fantastic talk on carbon debt (with a rather depressing 238 views at the moment; I hope more people watch...): [this video]
Agreed, this is an excellent talk. Main takeaway is to view the problem as debt which has to be paid off. Simply stopping new purchases will not pay off the debt. Above point summarized here, timestamp 22:15 - [this video] We currently have a one trillion ton carbon debt. As a though experiment, for a starting solution to iterate upon, this can be "paid off" with 20 billion trees / year, for 50 years. It would take 9000 drones, 450 staff, $80 mil/year. And a total land area half the size of Brazil. Using current technology. Compare this with alternative approaches being thrown around with price tags of 1 trillion+.
Frames CO2 as debt to repay; tree-planting by drone costed.
It looks like that article is 10 years old. Has anyone done this at scale? A more recent (this year) talk advocating for similar, but using drones [this video]
Recent talk advocating large-scale tree planting using drones.
Yes, even if we completely eliminate carbon emissions, our current carbon debt is around 1 trillion tons [1]. We'll need to remove that much carbon from the atmosphere within 50 years or so, given we stop all of our emissions today. [1]: [this video]
Source for the roughly one trillion ton carbon debt figure.
Related, for comparison: apparently planting 20B trees/year requires only $80M/year (!) and would pull down a trillion tons of carbon over 50 years (!): [this video]
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