Most studies say it's already too late to stop a lot of it. There's tons and tons of studies and models that say if we magically cut off all sources of climate forcing we'd still see an increase from the damage already done for centuries. We can obviously make things a LOT better for ourselves by stopping or limiting ourselves right now but a lot of damage is already done. Plus any significant changes will most likely take a decade plus to really get momentum and actually take place anyway.

That's why now you're starting to see a lot more research into mitigation rather than prevention cause we're starting to move into the "well how are we going to fix this" phase rather than the "we need to stop this from happening phase"

The biggest indicators are the oceans. Just take a gander at oceanic temperatures over the last like 25 years. since they absorb something like 95% of our thermal extremes we're seeing some bonkers changes out there...