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Geophysically, there are 3 pillars to climate stabilization:

1. Emitting fewer greenhouse gasses. Need to do that more than ever, but we are now in overshoot so…

2. Actively remove greenhouse gasses from atmosphere. Will need to do that, but land use and dirty energy trends away from net negative. Also, it’s a 100 year project once started.

3. Shade Earth. Not regions, The whole globe. There are two ways to do that:

a. Stratospheric aerosols b. Planetary sunshades in space, at Sun-Earth L1.

That’s the whole solution space, conceptually. As long as we continue to fail within that space, we will suffer compounding effects of unmitigated climate change.


> Actively remove greenhouse gasses from atmosphere. Will need to do that, but land use and dirty energy trends away from net negative. Also, it’s a 100 year project once started.

I once did the math, assuming we have enough resources to build a lot of solar panels. Assuming current efficiency levels of solar panels and current commercial feasible levels of direct air carbon capture (DAC), if we annually allocated an amount equal to our current annual solar panel production to building large solar farms dedicated to powering DAC plants, in about 150ish years those plants would be capturing each year an amount about equal to our current total annual emissions.

If we keep expanding solar panel production we could shorten that timeline and build more than just enough to breakeven. The area for those solar farms would be about 1/15th the area of the 5 largest subtropical deserts.

What would we do with all the carbon extracted? That's not really a problem. If we can't think of a good use for it, just mount the solar panels powering the DAC plants a few meters off the ground, convert the carbon to graphite, and dump it under the solar panels. Spread evenly it would only be a few mm thick.


Two of these things will definitely work. One of them is completely untested, poorly understood and with potentially massive consequences for the climate and food production.

Precisely! The world needs to spend 15 billions a year on reflective aerosols while it reduces emissions thanks to renewables.

This will not address the acidification of the oceans which is very bad but something is better than nothing.

Carbon capture is way too slow to work. It’s a rounding error.


Worth noting that aluminum is the most abundant metal of the Moon’s highland geography, thus excellent for bootstrapping beyond Earth.


w00t


This lowers p(doom) for me.

It makes sense that reinforcement learning on reasoning about coherent principles should bias toward principled action in real situations.

Probably also illuminates moral interpretability.


Philosophically, this looks like breaking the training data limit in the same way that humans do: by using an internally consistent view of the world to imagine new scenarios and integrate them into an updated worldview.


Feels like 1999 all over again. This time, I think it really is different.


It is insane that the Paris agreement requires a centered 20-year running mean of global surface temperature to define global warming thresholds.

That bureaucratic sleight of hand builds roughly a decade of delay into the system. Sclerotic by design.


Considering climate was generally defined as a 30 year window when I took earth sciences classes in the early 2000s I don’t think it’s a sleight of hand. Pretending that every minor outlier year in the span of 200 out of tens of thousands of years is an Armageddon-signalling catastrophe in order to secure more funding is far less genuine.


Missing from the article: Jared Isaacman offered to fix Hubble for free, and NASA turned him down.


>It basically seems like the risks involved aren't necessarily worth taking right now, seeing as Hubble is technically doing just fine.

*https://www.space.com/jared-isaacman-hubble-space-telescope-...


Best one-lesson favor I ever got was dimensional analysis in high school.

Do it, and most basic physics is trivial.


Hop David is the person on the internet who the author wants to talk to about whether their math on orbital tethers is correct.


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