HAVING GROWN UP in a family and a culture built around the ocean, Johnson has remained grounded through a combination of simple living and adventure. Among the surf crowd, the term waterman has become an honorific, like the Spanish patrón or the Japanese sensei. Surfing does not make you a waterman. Neither does a good tan or playing the ukulele or having a house at the beach.

Johnson's father, Jeff, is the waterman archetype. Now 61, the semi-retired contractor, who still surfs almost every

"I was a nature boy growing up," Johnson says. "Being out in the ocean all the time, hiking, camping, taking canoe trips with my dad—that's where it all comes from."

day, has a history of fearless experimentation in the water. Back in the seventies, he and a friend, Flippy Hoffman, inadvertently helped usher in the era of tow-in surfing by using a small outboard fishing boat to tow buddies riding an outrigger canoe into a 20-foot wave.

"I looked up to my dad," Johnson says. "It wasn't that he was big on rules or punishments; it was more like you knew you didn't want to disappoint him."

Pro surfing and making films were attempts by Johnson to preserve his waterman lifestyle while still making a living. Johnson admits he wouldn't have been able to survive financially if it hadn't been for his wife. He met Kim, 30, at UCSB during his first week at school. She was a double major in math and art and had a carved beauty and an energetic social conscience inherited from her grandfather, a progressive minister, and her grandmother, the director of a program that taught reading and English to recent immigrants.

After graduating from UCSB in 1997, Kim and Johnson traveled around Europe in a VW van, spent time in Hawaii, then set up house in Santa Barbara, where Kim earned her master's in education and became a high school math teacher. They were married in 2000 and now have a one-and-a-half-year-old son.

"Kim supported me as I traveled the world making surf films while she was on a teacher's budget," Johnson says. "That's the cool thing, to have somebody around I know and trust."

Johnson no longer needs Kim's income, but he relies heavily on her role as co-manager and her unflappable presence. When drunken girls in the New Orleans audience flashed their breasts at her husband, she cracked, "Hey, there's a child present!" When a huddle of girls on the street stop him for a picture, she never worries about the attention going to his head.

"Not at all," she says. "I suppose I might if he started to like the attention, but he doesn't. Besides," she laughs, "giving him shit is his brothers' job."

Back in Hawaii, the three Johnson brothers and their families live within a mile of the North Shore family homestead. "We're all such mama's boys, we couldn't stand to move away," says Johnson.

Once a waterman, always a waterman. But now Johnson is a waterman with money and cred. "I never really dreamed of being in a position where I had responsibility," he says, "but I wanted to do something positive with the attention I was getting."

So Johnson found a cause: the environment. "I was a nature boy growing up," he explains. "Being out in the ocean all the time, hiking, camping, taking canoe trips with my dad—that's where it all comes from."

In 2004, Emmett Malloy's cousin Chris, a surfer who is sponsored by Patagonia, introduced Johnson to Patagonia's One Percent for the Planet campaign, in which businesses promise to donate 1 percent of their net revenues for environmental causes. Johnson signed up—the first entertainment-industry heavyweight to do so.

He also trys to run an eco-sensitive tour, using biodiesel fuel for vehicles when possible and employing a recycling coordinator to organize bins and drop-off points at venues. He plans to offset carbon emissions generated by his current tour by buying renewable-energy certificates from NativeEnergy, a Vermont-based outfit.

Two years ago, Johnson and Kim started the Kokua Hawai'i Foundation, which has raised $250,000 to fund an educational program to teach Hawaiian kids about the islands' ecology and ways to preserve it. To support the foundation, Johnson and Kim sponsor the annual Kokua Festival on Waikiki, which features arts, music, and educational activities.

But Johnson is clearly uncomfortable talking about his stance as an environmental role model. "I'm not preaching," he says, "I'm just trying to set an example for anyone listening to my music."

This is Jack Johnson's struggle: how to be a star and still be Jack Johnson. He wrestles with this every day. The more he sees of America's celebrity culture, the more he thinks, This is not what I want my life to be like.

"I don't want to sound like some burned-out pop star," he tells me when I call for an update on his tour. "It's not like I want to give it all up and disappear. But I don't want to be at the same level I'm at now—I miss the surf trips to Australia and Indonesia too much."