I must not have read the same article that you did.

Because the article that you're linking isn't "debunking" climate change.

You seem to think that because they acknowledge that the Earth has seen much higher temperatures (hundreds of millions years ago), that it means there's nothing harmful about the Earth growing hotter now.

Carbon dioxide is really that master dial,” Tierney said. “That’s an important message … in terms of understanding why emissions from fossil fuels are a problem today.”

“We know it to be the worst extinction in the Phanerozoic,” Tierney said. “By analogy, we should be worried about human warming because it’s so fast. We’re changing Earth’s temperature at a rate that exceeds anything we know about.”

The study also makes clear that the conditions humans are accustomed to are quite different from those that have dominated our planet’s history. For most of the Phanerozoic, the research suggests, average temperatures have exceeded 71.6 F (22 C), with little or no ice at the poles. Coldhouse climates — including our current one — prevailed just 13 percent of the time.

This is one of the more sobering revelations of the research, Judd said. Life on Earth has endured climates far hotter than the one people are now creating through planet-warming emissions. But humans evolved during the coldest epoch of the Phanerozoic, when global average temperatures were as low as 51.8 F (11 C).

Without rapid action to curb greenhouse gas emissions, scientists say, global temperatures could reach nearly 62.6 F (17 C) by the end of the century — a level not seen in the timeline since the Miocene epoch, more than 5 million years ago.

So, TL;DR (because I'm sure the majority of the people commenting here won't actually read the article):

1.The Earth has had huge shifts in temperature.

2. In those temperature shifts, Carbon dioxide was the cause of rapid heating of the planet.

3. Rapid heating of the planet caused huge mass extinctions.

4. Humans came in during one of the coolest ages of the planet.

5. Carbon dioxide is now causing the most rapid increase of temperatures of the planet, ever.

6. If humans don't figure out a way to curb the rise in carbon dioxide, we will be facing another mass extinction event, where we will most likely die off.

Now, let me make it abundantly clear that I'm not agreeing with what is being claimed in this article.

What I am saying is that you have grossly misunderstood what the article was saying.

People who believe in climate change have never claimed that the Earth has not seen hotter temperatures. I have no idea why you would think this is a big "Ah-ha! Gotcha!" moment, because it's not.

So, for the love of little baby Jesus, please, please, please, do not run around trying to redpill normies with this, because, without a doubt, they will laugh in your face and then believe you to be extraordinarily ignorant.

And that doesn't really help anyone here, does it?