This is a nuanced question that depends on what "reverse" means. Here's the scientific consensus:
It's not "too late" to act — but some changes are already locked in
What's already irreversible (on human timescales):
•Ocean warming and acidification will continue for centuries even if we stopped all emissions today, because oceans absorb heat slowly and release it slowly
•Sea level rise will continue for hundreds of years due to thermal expansion and ice sheet melt already set in motion
•Some ice sheet loss (parts of Greenland and West Antarctica) may have already crossed tipping points
•CO2 already in the atmosphere will persist for centuries to millennia
What's still within our control:
•The rate and ultimate severity of warming is still very much in our hands. Each fraction of a degree avoided matters significantly for reducing harm.
•We're not choosing between "fixed" and "doomed" — we're choosing between different degrees of bad outcomes (e.g., 1.5°C vs 2°C vs 3°C of warming), each with very different consequences for ecosystems, agriculture, and human life.
•With aggressive emissions cuts plus carbon removal technology, it's theoretically possible to bring global temperatures back down over decades to centuries, even after overshooting targets.
The more accurate framing:
Climate scientists generally avoid talking about "reversing" climate change and instead focus on:
1.Stopping the warming from getting worse (reaching net-zero emissions)
2.Limiting peak warming as much as possible
3.Adapting to changes that are already unavoidable
4.Eventually drawing down atmospheric CO2 through natural and technological carbon removal, which could slowly reduce temperatures over the long run
Bottom line: It's too late to prevent all climate change — some is already happening and more is locked in. But it's absolutely not too late to prevent the worst outcomes. The difference between serious action now and inaction is enormous — potentially the difference between a disrupted but manageable future and a catastrophic one. Every tenth of a degree of warming avoided reduces risks to people and ecosystems.
Would you like me to go deeper into any particular aspect — like carbon removal technology, specific tipping points, or what "net zero" actually requires?