CNN teamed three of its top journalists, who traveled across four continents and 13 countries, to present a comprehensive four-hour documentary about the threats to the global environment. Over two nights in October, “CNN Presents: Planet in Peril” will take viewers to places they’ve never gone before, including some that may not exist even five years from now, such as the Carteret Islands in the South Pacific.

“They’re a chain of islands with about a thousand people living there, and they’re sinking,” said Dr. Sanjay Gupta, CNN medical correspondent, who joined forces with CNN anchor Anderson Cooper and Animal Planet host and wildlife biologist Jeff Corwin for the documentary series.

“The islands are disappearing because of rising seas,” Dr. Gupta said. “Regardless of the reason, people are being forced to flee, and many people are calling them the first environmental refugees in the world. Just to get there took five separate flights starting in southern China. We then had to take helicopters, and we weren’t sure where we could land.”

“Some documentaries convey alarming statistics and others utilize stunning cinematography, but ‘Planet in Peril’ brings it all together,” said Jon Klein, president of CNN/U.S. “This is a comprehensive and thorough evaluation of the state of our planet. We bring viewers right to the heart of the issue with CNN’s global perspective.”

The debut of “Planet in Peril,” shot and produced using state-of-the-art high-definition equipment, comes on the heels of the upcoming fall launch of CNN-HD, the network’s high-definition news channel.

The idea for “Planet in Peril” began with interest in climate change, but the project soon encompassed more than that.

“We had all been talking about the fact that this was bigger than climate change—these were things that were making themselves known and appearing and crystallizing in a manner that is shocking,” said Mr. Corwin, who had been doing reports for “Anderson Cooper: 360” on issues involving the environment or endangered species. “We have reached that stage of being at the brink, where many, many species are at the precipice, potentially tumbling into extinction. We have species becoming extinct at a rate of about 20,000 every year. That equates to the extinction level when the dinosaurs were wiped out 65 million years ago.”

For the three principals, “Planet in Peril” provided a unique opportunity to do important stories. “Jeff has his area of expertise; Anderson is very interested in this stuff generally,” Dr. Gupta said. “I was very interested in both the human impact and the medical impact. What we found is that there are connections all around.

“For example, species loss is a big concern in climate change,” he said. “But why are so many species being lost in Southeast Asia? While climate change is part of it, it’s not the entire cause. It turns out there’s poaching going on, and some of that poaching is going on in China because traditional Chinese medicine is so popular and they use things like bears and tigers and turtles, the very species that are threatened as a result of this 1,500-year-old practice. So there are other reasons than climate change.”

Mr. Cooper also saw the need for a broad-based approach. “Our goal was to report not only on individual issues, but to examine the interconnectivity of environmental changes,” he said. “Instead of simply delving into academic theories, we set out to document the actual changes taking place that affect the way we live our lives and the choices we make. The environment is more than just a niche news story; it is an issue that affects every living being and warrants greater attention in the press.”

For Dr. Gupta, one of the most challenging segments was an investigation of Lake Chad in Africa, which is shrinking. “It’s the sixth-largest lake in the world. It borders four different countries. Yet remarkably, it has shrunk by 90 percent in the last 40 years,” he said. “If you read most textbooks, magazine articles, literature in general, they say it’s because of climate change.

“We actually circumnavigated the entire lakebed,” he continued. “It took 17 hours of driving in the desert to get a better understanding, and a couple of things we learned are that farmers and fisherman are diverting water from Lake Chad. There’s water going out and there are also these aquifers that people are digging, pumping out hundreds of gallons of water a day. So climate change is certainly part of the problem, but in order to really tell that story, you had to travel the lakebed and understand that the entire culture has changed over there. There are other reasons why that lake is shrinking.”

Despite years of travel to remote locations around the world, Mr. Corwin still was stunned by what he saw while filming “Planet in Peril.”

“The series was a revelation from the moment we stepped in the field,” he said. “The first location was Brazil, and I have spent much of my life doing conservation research work in the rainforest, but it had been a long time since I had been in the field at that level. I was really taken aback by how much has been lost and how little is left. Brazil has lost a U.S. state in rainforest; 20 percent of Brazil’s rainforest is gone. That was incredible to me.”

Mr. Corwin became ill during filming in Southeast Asia, and in one instance his life was put at risk. “Anderson and I were doing a story on elephants that had been poached,” said Mr. Corwin. “We were telling the story of an elephant that had been caught in a snare and was burned and how they were rehabilitating this elephant to recovery, and in the middle of telling this story, the elephant decided to reach out and grab me and beanbag me around. He nearly tore the arm out of my shoulder.”

The impact of “Planet in Peril” on viewers could be dramatic. “I think a lot of people understand climate change theoretically, but I think when you actually can show them stories of how people are directly affected, it reaches people on a different level,” said Dr. Gupta. “It brings it home. What does it mean when tropical diseases that were once relegated to the tropics suddenly start creeping up into the States? What does it mean when a huge lake is suddenly no more? What happens to people? Do governments take them in, are they welcomed, are they pariahs? What does it mean to be an environmental refugee? There are visceral stories in ‘Planet in Peril.’”

“I’d like the audience to feel empowered,” said Mr. Corwin. “The last thing I or Anderson or Sanjay or CNN want is for people to feel helpless. … Despite the dire situation, I do not want people to feel that it’s too late. I do not want people to feel that they cannot make a difference.

“The most important piece of information a viewer can walk away with from this series is that, despite that they are just one among 6 billion human beings living on the planet, they will have an effect,” Mr. Corwin continued. “You have the opportunity to step up and make a difference. You need to change your ways, and every human being on the planet needs to think about being sustainable. That’s what I want people to absorb from ‘Planet in Peril’—it’s not too late to make changes.”

“Planet in Peril” premieres on CNN over two nights, on Tuesday, Oct. 23, and Wednesday, Oct. 24, from 9-11 p.m.

• Q&A: CNN’s Anderson Cooper on ‘Planet in Peril’
• CNN’s Peter Dykstra Touts New Technology’s Ability to Improve How Environmental Stories Are Told
• SEJ: The Growth of Green
• NBC News’ Thompson Stays Green
• SEJ Picks Right Environment to Meet
• Fighting Over the Freedom of Information Act
• CNN Teams Trio for ‘Planet in Peril’
• NBC Launches Weeklong Green Event
• Ken Burns Goes Back to Nature on PBS
• Sundance Focuses on Green Documentaries
• SEJ Panel Aims to Get Scientists, Journalists Working Together
• The Greening of News Corp.
• Weather’s Consumer-Driven Content
• Meteorologists Get Help With Science From Earth Gauge
• Weather Channel’s Heidi Cullen Calls Herself an ‘Infrastructure Junkie’
• Food is Crucial to Environmental Beat
• KRON4’s Clifford Created Environment Beat for Local Station, Web Site
• Environmental Reporting Key to KNBC
• HGTV Builds Green House
• Discovery Preps Planet Green
• Discovery Preps Series on Rebuilding of Greensburg as Green Town
• Discovery Branches Out Online
• Discovery HQ Goes Carbon-Neutral
• Maine Station Manager Takes the Heat
• Editorial: Media Giants Lead the Way to Green Future
  PROFILES OF SEJ FINALISTS

• SEJ Finalist has Independent Streak
• ‘The Green Monster: It Came From the River’
• CBS is SEJ Finalist with ‘Alaska and the Arctic’
• Public TV Documentary Spotlights Rescue of New Jersey Wetlands