It could make the earth too hot for SOME humans, as in it will force the human population to decline, something guaranteed not to be pleasant.
We're a long way away from any prospect of climate change making the earth unable to support the species homo sapiens, and it's a waste of breath talking about it.
I mean, plenty of people are already dying of starvation and dehydration, but you know what I mean. Wasn't that the backstory to Battlefield 2142? Arable land either became desert or ice and everyone went to war over a few breadbaskets?
They thrived. Plants thrived. The danger is in the change part.
(yes there are cold-blooded mammals and warm-blooded dinosaurs, but they're rare exceptions)
The TL;DR versions of nuanced articles too frequently consider only humans to be significant. We're part of a big ecosystem, and the collapse of that system will inevitably take us down with it.
Everything from Chicken to Server farms has trouble with ventilation and AC.
And the list goes on and on. 10 years ago when the last ski lift in my home town closed for good I thought: "Wow climate change is really here" but now my wife and I are really concerned.
The actual situation is that the petrochemical companies are spending a large amount of money on spreading FUD to obscure just how dire the situation is. They are immensely wealthy, meaning that they are immensely powerful. Concerted action to combat rising carbon dioxide and methane levels would destroy them. So, they are spending a lot of money fighting efforts to control fossil fuel use.
Since the science is completely clear and unambiguous and there is no reasonable doubt whatsoever, the easiest tactic is to fog the issue. To spread suspicion that there is contention. To pay for contrarian researchers to say it's unclear.
Additionally, it is important to realise that our times are ones of major cuts in funding for science, basic research, academic institutions, and so on. This means that research organisation and individual scientists have to chase industry sponsorships.
The majority of geologists, mineralogists, palaeontologists and so on work for petrochemicals companies, or work for companies or organisations that are funded by petrochemicals companies. So they are muzzled: they are not allowed to speak.
I personally have spoken to 2 such individuals recently. In public, both say "it's unclear, there is conflicting evidence," etc. Their employment requires this.
In private, off the record, they are blunt. "We are fucked. Completely, totally fucked, beyond any hope of remediation or moderation."
No, it's not controversial or unclear.
But there are legions of conspiracy theorists, religious advocates and assorted nut-jobs who delight in seizing on any hint that it's not certain and spreading FUD.
And there are those who don't care because it's clear that stopping this process will be vastly expensive and very bad for the stock markets and so on, and they care more about money than the planet. This seems insane to me but I know such people personally. It's quite common.
Equally, media organisations come in 2 forms: those committed to balance and impartiality, who convey both sides' views, 50% each -- the real science (99%), and the paid lobbyists and fringe lunatics (1%). And the other kind, who spread lunacy (InfoWars.com etc.) or what they are paid to spread (Fox News, News Corporation, etc.)
So the media representation is that there's controversy and it's not certain.
There isn't. Go look at the scientific view, and we are completely fucked. We are in the exponentially-rising part of the curve of the 6th great mass extinction event and it is not meaningfully possible to stop it.
It is, of course, possible to work to make it not quite so bad, but it will cost trillions of $/€/£/whatever. The rich don't want that. They're mostly old. Companies are immortal or nearly, but they, by design, chase the easy money and the safe bets. The industrial revolution and the economic system of the world is based on machine power replacing human and animal power. It will continue to pursue that until it collapses.
At this point, changing that requires replacing the current military-industrial complex and economic system of the whole world. That's as hard or harder than cleaning up our act, so it's not likely to happen -- not until it's too late.
If the worst does come to pass, I'm sure it will alter life as we know it, but the danger would probably be more to animals that can't compensate with technology like we can.
In this case there are 8 billion members of the apex species. Humans will survive, but it's not going to be much fun until the new normal emerges.
Technology will help, but it will only cushion the fall, not prevent it, and only if we react quickly enough to reduce the impact. When enough people start starving they will start looking for food and water wherever they can find it, and they won't be very charitable towards those who they believe caused the problem.
From simple models -- e.g. foxes and rabbits: https://niko.roorda.nu/computer-programs/fox-rabbit-theoreti... -- to more complex web models -- http://journals.plos.org/ploscompbiol/article?id=10.1371/jou....
In any such models, sometimes, with extreme population growth of any one member species, the result can be collapse so severe that that species goes totally extinct.
We're not looking at a simple redistribution. We're looking at exponential explosions, and they tend to be followed by a total collapse.