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Comment by goatlover | Hacker News Reader

Why is it destruction and not just it will be more costly to adapt? Why suppose that we can't figure out a way to scrub C02 from the atmosphere, or offset it some other way? Why can't humanity, who managed to survive an ice age with stone aged tools, figure out a way to survive a warmer planet with modern tech?

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Thermodynamics comes into play. Because the entropy of a pure gas increases rapidly as it diffuses into a mixture, it will always require massively more energy to scrub CO2 from the air than you get from burning the carbon in the first place.

Scrubbing would only become possible if we either:

- develop unlimited free energy (fusion, or incredibly cheap solar)

- let plants do the work for us, harvesting the Earth's tremendous isolation.

Either of these solutions almost implies that the climate battle is already won. In the first case, if clean energy is cheap enough to scrub carbon, then it is cheap enough to displace all other power sources. In the latter case, the slow pace of photosynthesis means we'd have to stop burning carbon (and stop burning forests) for a long time until CO2 concentrations stabilize, which is exactly what the Kyoto protocol was all about.

There's also geoengineering. While it's risky and controversial, it will become a real option if we are faced with bad enough consequences otherwise. Doomsday predictions assume we can't figure out a way to adapt or counter the climate change.

I agree. But I haven't heard a plausible geoengineering plan proposed yet. This is the part where engineers should be able to provide an answer today, achievable with our existing technology. It isn't enough to wave one's hands and assume that a solution can be developed someday when we're in deep enough trouble.

With our technology, it's still considered a nation-scale accomplishment to build a bridge spanning 55 km, or a dam spanning 2 km. Those kinds of engineering accomplishments are currently the likes of which most nations can only dream.

All we can currently do on the planetary scale is resource extraction -- fishing, strip mining, and deforestation. And accidentally altering the atmospheric composition of course.

I guess we can try to cover the entire ocean in floating white plastic pellets, to increase its albedo? That would probably work.

Cold is easier to survive than heat. Humans can't do any useful work outside or even survive once the web bulb temperature reaches a certain point. For example at 90% humidity the temperature limit is 35℃. Some tropical areas will become essentially uninhabitable.

https://insideclimatenews.org/news/02082017/heatwaves-deadly...

>For example at 90% humidity the temperature limit is 35℃.

This seems weird. A lot of tropical places are both hotter and more humid than this limit, and people seem to have adapted.

>A lot of tropical places are both hotter and more humid than this limit

Where? As far as I can tell, the highest wet-bulb temperatures are around the Persian Gulf, and although they sometimes come close to the human survival limit, they do not yet exceed it.

https://blogs.ei.columbia.edu/2017/12/22/humidity-may-prove-...

https://www.timeanddate.com/weather/india/kolkata/historic?m...

Temperature exceeds 35C, and humidity exceeds 90%, but not both at the same time.

I can find quite a few examples of both happening at the same time. For example, look at May 30.

I'm not seeing it. Temperature peaks at 37C, but humidity is only 57% when it happens. Humidity peaks at 94%, but temperature is only 29C when it happens.

You're right.

Some tropical areas becoming uninhabitable doesn't sound like doomsday. It sounds like people have to be relocated, or stay indoors during part of the day or season. Which might mean increased automation in that part of the world to replace manual labor.

Is that supposed to be some kind of joke? We're talking about mass migrations to cooler areas. Wealthy people might be able to crank up the AC and hide inside but the poor will just die. If the predictions do come to pass then it literally will be doomsday for parts of the world.

So doomsday for part of the world or doomsday for the human race? The parent's claim was we have ten years or we face doomsday without qualifications.

As for migrating to cooler climates , what is the time scale? A century? 50 years? 20 years? What about technological solutions that come into existence during that time frame? Are we going to discount them?

Doomsday implies the human race can't adapt.

Nearly impossible to change the global capitalism & imperialism we're currently in. We're going to die.

Edit: people flagging valid & non-harmful opinions just because you don't like them needs to stop.

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