Ignorance is bliss, but I'm that kind of intellectual egotist who would rather be correct than happy
Imrahil wrote:I think they'll invent atmosphere regulation technology on a massive scale which will let the human race 'off the hook' to some extent, averting all the worst case scenario stuff. Also, they'll work out how to grow sustenance cheaply in synthetic farms so famines will be a thing of the past. In general, understanding of what the body needs to survive will dramatically increase, and the physical amount of food we consume will fall significantly.
I think you're right on the latter two points technologically, the problem is in real world distribution. Globally we already produce more than enough food for every person on the planet, and yet regional famines, malnutrition and starvation are still real issues that affect millions. Even without new technologies such as artificial meat and vertical farming we could provide for everyone, but our global systems aren't set up to prioritise that - there isn't particularly reason to think that the emergence of new technologies will magically solve that.
When it comes to geoengineering efforts (that are all essentially about regulating the atmosphere), there are huge uncertainties around any potential technology and its application. The climate and the Earth's ecosystem are hugely complex and inherently chaotic, so I think we should expect significant unforeseen side effects from any serious geoengineering effort. Almost all of the proposed technologies that get seriously discussed are very controversial, and its likely one or several nation states will be forced in reacting to the effects of climate change to jump into one without knowing all of the risks. It may even be adversarial - engineering a beneficial climate in one region may adversely affect another, for example in changing patterns of rainfall making one region wetter but at the expense of another that becomes drier. There are already real-world analogs to this where rivers and lakes cross borders and where projects such as water use and damming are beneficial to the country implementing those projects but harmful to others.
Imrahil wrote:I guess the bigger problem will be sheltering all the humans on this planet. And what quality of life there might be when it gets truly crowded. How will humans cope psychologically when hundreds of millions of citizens live in the same geographical area that dozens of millions currently do?
Contrary to popular belief the rate of world population growth is in decline. According to the UN (and me just looking it up on Wikipedia) world population growth peaked in 1968 and world population is expected to peak around 2100 at only 11 billion (we're at 7.8 billion right now). So this is actually less of a problem than you might think! It is a problem for capitalism though, being a system built on the premise of never ending growth.
Imrahil wrote:Preventative healthcare will be incredible. The concept of disease and infection could become a thing of the past. They'll probably fully understand the formation of cancer and nullify it before it even develops, etc.
I agree that we will continue to see huge and beneficial strides in medicine! Preventative healthcare is a bit less certain because that comes down to political will as much as medical breakthroughs. We're already overdue a preventative healthcare revolution - many health issues today could be tackled with preventative healthcare that is already possible, but isn't done, like having people routinely screened and given health check-ups.