After two and a half years sailing around the planet, the Hokule‘a is almost home — but its journey and mission are far from over, says Nainoa Thompson.

Some of the Hawaiian voyaging canoe’s hardest sailing still lies ahead en route to Easter Island, also known as Rapa Nui. Finding that remote speck of land in the vast Pacific remains one of the toughest challenges for any traditional navigator. There’s also still much work left to train Hokule‘a’s next generation of navigators and captains.

And Thompson, a pwo (master) navigator and president of the Oahu-based Polynesian Voyaging Society, says the group won’t know if its Malama Honua (“care for the earth”) worldwide sail succeeded in spurring more action against climate change, runaway pollution and other environmental hurdles until the canoe and its crew return safely to Hawaii.

“I sense that people think we are home, but we’re not,” Thompson said Wednesday as he sat in the shade aboard the Hokule‘a’s occasional escort vessel, the similarly double-hulled Hikianalia, now at Sand Island. “The most mistakes are made in the last mile when you let down your guard.”

He added: “We’re driving up physical training. We’re making everybody get their medicals. No mistakes. We’re working really hard for the last segment, to make sure we do it right.”

The 3,000-mile sail into the wind from the Panama Canal to Easter Island and re-entry into the Polynesian Triangle this month will be Thompson’s last leg of the voyage, he said.

For the next six months and final seven legs of Malama Honua — a journey back into the open ocean through the Galapagos Islands, Easter Island and French Polynesia — he and other veteran voyagers aim to step back and let a new generation of captains and navigators get the canoe home to Hawaii.

Longtime Hokule‘a captains such as Bruce Blankenfeld and Kalepa Baybayan will pass their duties to experienced crew members such as Keahi Omai, a longtime Honolulu police officer, and veteran Maui waterman Archie Kalepa. Ka‘iulani Murphy, a Honolulu Community College instructor, will serve as the lead navigator from Tahiti to Hawaii, Thompson said.

Meanwhile, apprentices such as Haunani Kane, a University of Hawaii geology and geophysics graduate student; Jason Patterson; and Lehua Kamalu will use the remaining legs to hone their skills using the stars, waves and other natural cues to navigate across hundreds of miles of ocean wilderness.

The navigation apprentices also must be willing to be community leaders back on land, Thompson said.

“This younger generation has got to step up to be the voice,” he said. “It’s going to matter to young people to see other young people are so successful and world-class.”

When the Hokule‘a returns to Oahu, in addition to a large celebration planned at Magic Island, a “graduation” ceremony for the apprentices featuring cultural protocols will occur at Kualoa, Thompson said.

The voyaging society also plans to sail the canoe, a more than 40-year-old replica of traditional Polynesian sailing vessels, to 29 ports across Hawaii this year and next year to thank the communities for their support — as well as to get a better sense of the local efforts to protect the islands’ environment.

“Our job when we get home is not to be the lead,” Thompson said Wednesday. “It’s not … to find the elements of sustainability because people are already doing it. Our job is to connect them. It’s to build the relationships.”

Since May 2014, Hokule‘a volunteer crews have steered the vessel through some of the world’s riskiest places to sail, including the Indian Ocean and the South African coast, to help advance the Malama Honua mission.

Crews met twice with former U.N. Secretary-General Ban Ki-moon — first in Apia, Samoa, in 2014 and then in New York City in 2016. From the first meeting, they secured a pledge to better protect the world’s oceans prior to the 2015 signing of the Paris Agreement to curb climate change.

They’ve also collected 11 declarations by governments and nongovernmental organizations for marine protection along the route, according to the voyaging society. This includes a collective of dozens of Hawaii public agencies, nongovernmental organizations, businesses and schools that signed the legally nonbinding “Promise to Pae‘aina” — a pledge to better manage the state’s marine resources.

But the larger political climate that Hokule‘a faces on its return journey — as it sails against stiff winds and waves toward Easter Island — is different from the one it saw when it left Hilo in 2014. U.S. President-elect Donald Trump has indicated he might somehow upend the Paris climate deal, a treaty that reflects the stated values of Hokule‘a’s Malama Honua voyage.

Thompson said he can’t worry about the shifting politics. In the canoe’s journey of more than 35,000 miles so far, its crews have encountered thousands of people concerned with protecting the environment for future generations, he said.

“What we’re finding is there’s another culture out there. … It has nothing to do with race, it has nothing to do with the boundaries of geography, it has nothing to do with political systems,” Thompson said while sitting aboard Hikianalia. The double-hulled vessel will soon depart Sand Island to rejoin Hokule‘a in the Marquesas Islands and escort her on the journey home.

“It’s a culture that’s global. It’s about values; it’s about caring; it’s about compassion and kindness,” he added. “The more that the political system is (what) we would define as adverse, the more you’ve got to sail. I don’t like the political climate and culture that I see, but I never did. Not that I don’t care, but that’s not going to stop this community from doing what it believes in.”