Typhoon Haiyan: American storm chaser helps float survivors to safety

American storm chaser Josh Morgerman went beyond merely capturing the destruction of Typhoon Haiyan in Tacloban on video.

When Morgerman went to the Philippines to document the storm, the last thing he expected was that he'd put down his camera -- and save lives.

"As the center passed just south of the city, the bay just rose up and swept across the downtown area," Morgerman told CBS News' Bill Whitaker. "All of a sudden the hotel was in water and it was just rising rapidly. The people in the first floor rooms were caught by surprise. So they were in the rooms with the water rising, like these death traps essentially."

Complete coverage: Typhoon Haiyan

Morgerman and his colleague Mark Thomas began floating people to safety on mattresses. Morgerman said, "These people were in their rooms, they smashed the windows and they were screaming for help. When you see someone suffering like that, they're going to die if you don't do something, you don't think about it. You just go."

Morgerman had raced to the Philippines to get as close to the eye of Typhoon Haiyan as possible to collect scientific data and images.

He'd been in more than 20 major storms. He says Haiyan didn't seem like a monster at first.

"Picture the downtown area of a city inside a tornado for an hour - I mean, that's what it was like," Morgerman said. "We were in a four-story, solid concrete hotel, like one of the most solid buildings in the city, and it was trembling and shaking. Wreckage from other buildings was smashing into our building, and it was like thundering and trembling."

That's when Morgerman and Thomas jumped in to help. Thomas didn't see the dangerous debris hidden in the water.

"When he was trying to pull a woman out of a window and there was a piece of roof of a nearby building, part of it had blown into the courtyard and was under the water. It was a rusty, old piece of tin, and it ripped his leg wide open, and I don't mean a cut, I mean just cut to the bone," Morgerman said.

It took 48 hours, but Thomas made it to a hospital, and was evacuated via an air transport. He's now home in Taipei, facing a series of surgeries.

Morgerman went to document one of Earth's biggest storms and ended up facing one of the biggest challenges of his life.

"You can really understand why ancient people, when they experienced things like this, they thought a God was angry and punishing them," he said. "Because it feels that way. It feels angry, it feels like it's out to get you. It's serious stuff."

Watch Bill Whitaker's full report above.