(Not to mention that solving Mars problems are likely to yield novel solutions to Earth problems, ones which we might never discover without thinking about things with an unusual perspective.)
Economics will singlehandedly take care of the "radical change" you seek.
And wouldn't you know it, these existing solutions are already on an exponential growth curve and cost decline. They have been for ages. We're on the right path right now; sadly most people find it difficult to think beyond linear growth.
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[To be clear, here I am responding to the challenge of bringing greenhouse gases emissions to a level which ends the rise of global CO2. It's a solved problem with lag time. The collapse of biodiversity is the political and sociological problem I referred to in a previous post.]
Scale is the problem.
> Once we have enough solar panels, wind turbines and battery cells, a tipping point is reached where the cost of renewable energy plummets so hard that fossil fuel energy becomes catastrophically uneconomical
The radical change I'm referring to is the drastic cut in energy consumption to make renewables work at our current scale. I suggest you have a look at the latest IPCC report [0]: we won't be carbon neutral without reducing our energy consumption, not "simply" replacing a source by another for each use, reducing it. That means doing less things, which no one plans on doing.
Not even to mention that some non negligible parts of our economy don't have a technical solution yet, the aviation industry for instance.
> a solved problem with lag time
I don't understand what you mean by that as it seems we are not on the right trajectory to avoid a catastrophic outcome...
[0] https://www.ipcc.ch/report/sixth-assessment-report-cycle/
Unnecessary. You’re thinking linearly. We don’t need to cut energy consumption, it will be met and exceeded by the current exponential growth of renewables and storage. The “we have to do less” crowd are wrong and bad at math.
Aviation isn’t a solved problem yet but that’s still less than 3 percent of fossil fuel sourced greenhouse gas emissions. There are far more pressing concerns like banning domestic fireplaces.
I would be more concerned about the ocean shipping industry, one which is just screaming out for nuclearisation, but of course that would be protested by ignorant faux-environmentalists who care more about telling others what to do than what’s actually good for the planet. (For some light entertainment, read up about fractional distillation and learn about exactly what it is most cargo ships burn. It ain’t avgas, that’s for sure. But nobody cares because intercontinental trade doesn’t work as well as commercial aviation as a target for class warfare.)
> That means doing less things, which no one plans on doing.
No one plans on doing that right now. But once we divert the attention of astrochemists away from studying the terraforming of Mars and towards the intersection of politics and sociology, I’m sure they’ll come up with the solution.
> it seems we are not on the right trajectory
It would seem that way if you think linearly.
Physics, not maths. You can sustain exponential growth as much as you want without physical limits. If that's where your confusion comes from, you can read some vintage Meadows.
> It would seem that way if you think linearly.
Even the optimistic scenarii put us in a bad position... ignore evidence as much as you want, it won't make it true.
For precisely this reason?
We can't stop asteroid impacts. We can't stop a well-adapted plague, either (Ref: Covidiots). We have dictators with nuclear weapons that we can't stop. etc.
Having a self-sufficient colony somewhere other than Terra is almost certainly the first step toward avoiding a "Great Filter" event.
By this logic we never go. There will always be giant seemingly insurmountable problems. If we solve climate change there will just be another, and another, and another. Life is a never ending fight against entropy. There will never be a time when we have it all figured out.
Secondly it’s entirely possible that the stuff we learn trying to survive off world will be applicable to making life here more sustainable. It could force us to figure out how to run industry efficiently with a very high percentage of material recycled, and how to run an economy without a lot of low entropy ecosystem to draw from. Also no fossil fuel. They don’t exist. We’d only have nuclear and solar really.
We can't even fix the problems on our first planet. How (and why) can we even begin to think about another one?