Climate

The short version is as the title suggests, warming accelerating pretty dramatically, and based on recent studies we're fast approaching a hump that if we cross over, would likely result in a runaway situation that could not be fixed on human timescales. It's getting so bad even business analysis of the issue is suggesting drastic changes, such as not waiting for market forces to transition away from fossil fuels, but instead suggest governments globally super-charge the build-out of renewable energy sources.

What isn't said in the video: Basically unless we get off capitalism very soon (especially combined with the knowledge from a different study that suggests the atmosphere may become toxic to humans in the later half of this century), we're potentially looking at mass extinction much sooner than expected if we continue with our current way of life.