SUNSET BAY STATE PARK — Some will plant 350 trees, say 350 prayers, throw 350 Frisbees or light 350 candles.

Others will play 350 minutes of music, hold rallies and make art.

And in an island country where the threat of global warming and rising sea levels is very real, 350 scuba divers and snorkelers will join hands under the sea.

Philip Carver plans to walk.

In support of the international 350 effort to spread the word about climate change, the Salem-based scientist left Sunset Bay State Park with two friends Sunday morning, to walk as many miles from the South Coast to Portland’s Pioneer Square. That will be about 10 miles a day up the Oregon Coast for the former Oregon Department of Energy analyst to reach Portland on Oct. 24, for the International Day of Climate Action and a downtown rally.

“We’re doing this for our grandchildren, because this is the world they’ll live in,” Carver said as he packed up his campsite.

If things don’t change, “We’ll be constantly struggling with drastic climate change.”

According to www.350.org, humanity needs to quickly get below 350 parts per million of carbon dioxide in the atmosphere to avoid runaway climate change. We’re now at 385.92. The Web site shows that people in 119 countries have 1,552 events planned for the day of action next month.

In addition to walking, and wearing signs touting the 350 Web site, Carver, along with 25-year-old Courtney Collins of Corvallis, and driver Carol Reece who is toting the walkers’ supplies in a mini-van, will make appearances at businesses, churches and public venues along the coast and Columbia Estuary, to discuss the impacts of climate change and what people can do to reduce carbon emissions. The first talk, held at Java Jones Coffe House in Empire, didn’t draw a crowd, but Carver hopes to see more faces at the next 12, including one planned at the Reedsport Public Library on Thursday.

“Oregon faces catastrophic forest fires and summer droughts, because of reduced runoff from glaciers that won’t exist anymore,” Carver warned. “If we don’t reduce emissions in the next two to three decades dramatically, we will likely lock in six feet of sea level rise per century for the next thousand years.”

The 58-year-old, who has a doctoral degree in natural resource economics, said climate change is especially concerning, because according to the Intergovernmental Panel on Climate Change, hundreds of millions of people will be displaced in this century.

In the Maldive Islands in the Indian Ocean, President Mohamed Nasheed announced last November that his government plans to save money for a new homeland, if climate change causes the low-lying island nation to sink into the sea.

People are skeptical of what part humans have played in the problem, Carver said. One answer is teaching them to reduce their carbon footprints. That means driving less, recycling, reusing items and eating locally.

“We’re going to have to drive smaller vehicles, live closer to jobs, schools and shopping,” Carver said. “Pretending it’s not here won’t make it go away.”

After walking about 16 miles on Sunday from Sunset Bay, and across the McCullough Bridge, before returning to Java Jones for his presentation, Carver and his small team seemed chipper but tired from the day.

A former Americorps volunteer at an environmental middle school and friend of the Carver family, Collins said she became involved with the 350 effort to help Americans re-evaluate how they live and how they impact their environment.

“This is a way to help people realize and just kind of confront their lifestyles,” Collins said.

Reece, the only person in Carver’s three-person party who won’t be walking, recently went through back surgery. But she said that couldn’t keep her from participating in the 350 effort. Like Carver, she said she’s doing it for her grandchildren.

She wants to “prove to myself that I can do it, to prove to everybody that I can do it and to help Phil spread the word,” Reece said. “I just hope we can help make a difference.”