The Hokule‘a’s sister canoe, the Hikianalia, is scheduled to depart Wednesday, weather permitting, for a 2,500-mile voyage to California. Its arrival in early September will coincide with a Global Climate Action Summit in San Francisco.

The crew will bring a message from Hawaii about the importance of caring for the oceans and “Island Earth,” the Polynesian Voyaging Society said in a news release.

The roughly 30-day voyage, “Alahula Kai o Maleka,” honors the alahula — “frequented pathway” — between Hawaii and California and will demonstrate the important relationship between humanity and the natural environment.

The Hikianalia, a modernized version of the traditional voyaging canoe, is powered by the wind and sun, and uses traditional Polynesian navigational tools rather than GPS or other modern instruments. An electric motor, powered by solar panels, is contained in each hull.

Lehua Kamalu will captain the vessel, sailing through the Great Pacific Garbage Patch, a gyre of marine debris in the central North Pacific, and on into San Francisco Bay. The canoe and crew will engage with Bay Area communities and later head to San Diego before returning to Hawaii in December.

The voyage’s focus is on the critical need to protect the world’s oceans.

Polynesian Voyaging Society President and master navigator Nainoa Thompson will speak at the climate summit, at the invitation of California Gov. Jerry Brown, on the subject of “Healthy Oceans.”

Leaders from around the world will gather Sept. 12-14 for the summit, which will focus on commitment to taking action on the dangers of climate change.

PVS will team up with the Ocean Voyages Institute, The Nature Conservancy and Education Incubator to conduct science projects on the voyage.

The vessel’s science and education specialist will collect a half-liter of water a day while at sea to be tested in San Francisco.

Ocean Voyages will provide tracking devices to tag onto large garbage pieces found in the Great Pacific Garbage Patch.

The crew will also check the stomach contents of fish caught along the way and take dorsal fin samples.