It's 2024. Time to start acting like climate change actually matters [California examples]

Plus, current climate change has seen a velocity across a mere century that prior events took tens of thousands of years to achieve.

This imparts an “inertia” to our current climate that - even if we stopped on a dime, right now - will lead to conditions that may have most of the planet outside of the polar regions as being uninhabitable year-round due to chaotic weather and lethally high wet bulb temperatures that AC is simply unable to handle.

And if we don’t stop; if we continue on our “business as usual” path for another 10 or 20 or 30 years, said inertia could conceivably push the entire planet over into a full-blown Venus Scenario, wiping all life from the face of the planet.

Warming trails CO2 by 15-20 years. We are now seeing the 1.5℃ of warming of 2003, when Windows XP was released. If we hit CO2 levels that predict 5℃ of warming, humanity has essentially dug its own grave, the planet will (once warming catches up) no longer have any carrying capacity for us to survive in sufficient numbers. If we hit CO2 levels that predict 8-10℃, we run a non-trivial possibility of a tip-over into a Venus Scenario.

Prior events took many tens to hundreds of thousands of years, allowing entire ecosystems to migrate to and from the poles. This allowed the biosphere to “put the brakes on” warming itself because they never stopped being robust sequesters of CO2.

We don’t have that in play, here. Entire ecosystems will die in-place because they simply don’t have the time to migrate. We will see extinctions on a scale never before seen in the geological record. And the very robust biosphere that saved the planet in prior warming events will be commensurately weakened in this one, likely to the point where it cannot effectively sequester sufficient CO2 to stop the warming.

TL;DR: as a species, the likelihood that we are all endlings is uncomfortably high. Humanity may not see the year 2100, and will most likely not see the year 2200.

Lots of things would be great to have done in the past. The best we can do now is today.

Not really. People are expected to be stewards of creation; it's entirely possible to be a poor steward who does horrible damage.

The Holy Father ends his Exhortation with a reminder that “emissions per individual in the United States are about two times greater than those of individuals living in China, and about seven times greater than the average of the poorest countries.” He goes on to affirm that “a broad change in the irresponsible lifestyle connected with the Western model would have a significant long-term impact. As a result, along with indispensable political decisions, we would be making progress along the way to genuine care for one another” (72).

That is from the Pope of the Catholic Church making up half the Christians in the world.

Islam also has a lot to offer in that respect.

facts

too late for zero impact. Not too late to stabilize temperatures.