I've seen the hypothesis that the ocean's acidity will rise and it will be the end of the world (again).
I'm not a scientist, but yeah if that's true then it is a concern.
Having said that...what happened all through the Earth's history when CO2 levels were MUCH higher?
Did the oceans "die"? Or did life thrive?
Science tells us that when temperatures were warmer for instance...that more life existed and thrived on Earth than at any other time.
Historically we are not at the highest levels. Not even close. But since man has only been on Earth a very short time...it could very well be that CO2 could DOOM us all.
My opinion (as always), is that nature will adapt. The world will keep on turning. And mankind will exist until the next "extinction event" (meter or huge volcanic eruptions worldwide)
And then some other species will become the predominant life on Earth.
And that cycle will continue for a few billion more years until the Sun's life cycle is completed.
THEN, that will be... the end