I'm not sure this is the forum to provide evidence to what is obviously true.
Around 1950 the global emissions of co2 from human causes was about 5 billion tons. It explodes after 1950, hockey stick like growth and is now about 35 billion tons.
Humans have produced more co2 in 70 years than we have since we started to walk on two feet.
The basic premise of your argument is flawed. You’re asserting that we can only know about climate change after it happens. That’s not true. We can predict climate change will happen before it actually happens by understanding the relationship between CO2 and global temperatures.
Take something like general relativity for example, which was first theorized in 1915 and predicts things that we're only validating today. It's completely possible to predict something before it happens by understanding the underlying mechanisms of its action.
Around 1950 the global emissions of co2 from human causes was about 5 billion tons. It explodes after 1950, hockey stick like growth and is now about 35 billion tons.
Humans have produced more co2 in 70 years than we have since we started to walk on two feet.