INDEPENDENCE (AP) — Often, the kind of videos that blow up on YouTube involve scantily clad girls, or stupid pet tricks.

But a nine-minute, 33-second video on the perils of global warming made by Central High School science teacher Greg Craven has zoomed to the top of the YouTube heap, with 4 million views worldwide.

That’s roughly 500 times the population of Independence. That puts it near the top of YouTube’s all-time list for views in the news and politics category, despite competition from videos featuring Britney Spears, Satan’s face in a 9/11 explosion and an Alabama leprechaun.

The video is a worldwide appeal for action on climate change before it’s too late.

Craven’s argument is that debate over whether or not humans caused global warming is pointless; instead, Craven suggests, “the risk of not acting far outweighs the risk of acting.”

On the one hand, regulations to counter global warming trends could trigger an economic downturn, Craven posits. But at its worst, climate change could bring droughts, famine, floods, dust bowls, economic collapse and the displacement of millions.

The potential consequences are severe enough, Craven says in his video, to make “Al Gore look like a sissy Pollyanna with no guts who sugarcoated the bad news.”

Since his video exploded, the 38-year-old family man has sifted through some 7,000 comments and discussions, mostly critical.

“My toddler drools more cogent arguments,” one said.

Others are complimentary, saying they like his “inescapable logic.” Students at Independence High say Craven is “wacky” and “animated”, making even potential dry subjects like chemistry interesting.

After posting the first video, took a monthlong break at his wife’s insistence, then spent six weeks producing a 44-part, six-hour sequel, “How It All Ends.”

It includes small explosions, silly hats Craven bought in a Nepalese tourist mart and a script totaling 70,000 words.

After all this, life is changing for Craven. He might write a book. He’s shifted to part-time teaching after seven years to spend more time with his family.

The sequel’s introduction has gotten more than 500,000 views, most on break.com.

The backup videos, wonkier than the originals, have far lower totals. That’s disappointing, Craven says. “But I can look my kids in the face years from now and feel OK, that I did everything I could — even if the carbon has hit the fan.”