The Earth goes through natural cycles of warming and cooling.
Data from different places tells us this.
It also suggests that we'd already reached the peak, like 120,000 years ago, 220,000 years ago, 320,000 years. After each even the temperatures went down again. Except this time.
And yet it “stayed warm” long before the industrial revolution which means it’s perfectly natural.
Not necessarily. The spikes in temperature rises were not just up down. The first one 400,000 years ago was up, up a bit, up a bit, hit a peak, then down. The peaks are lasting a certain period of time, not always equal. But where you see a peak maybe 10,000 years ago, and then a drop, and then going up a bit and down a bit suggests that the downward spiral was on.
It's possible that during this drop we're going through a natural rise. I'm not going to say for certain that something should be happening. You might be right or you might be wrong about that.
The issue here is one of other stuff. Simple "It's getting warms" or "it's getting cooler" isn't the issue here.
This is the issue, we don't know the impact of what we're doing on the planet.
Mao decided that the pesky birds were eating the crops. So he had Chinese peasants go and kill the birds. What happened? The insects became prominent and ate MORE of the crops. He couldn't see what would be the cause of what he was doing. The same stands for us on pollution levels.
The first worrying thing is that the oceans are changing rapidly due to taking in more CO2. In the past this probably happened also, but probably not so quickly. Sea life could probably adapt OVER TIME, but maybe not over a shorter period of time. If the ocean life dies, the oceans will not only stop taking in more CO2, they'll start RELEASING CO2 into the atmosphere. That alone could be catastrophic, if it were to happen.
Will it happen? We don't know.
If you just off a cliff, will you land in the sea and swim to safety or hit the rocks and die? Would you take the chance on jumping without knowing it was safe?