Environmental and astronomy experts are urging residents across the state to reduce outdoor lighting to prevent the spread of light pollution.
Light pollution, caused by excessive artificial lighting, is not only a nuisance to neighbors but poses a growing threat to both the astronomy industry and many endangered animals, speakers at a lighting seminar on Oahu said Wednesday.
University of Hawaii astronomer Richard Wainscoat said the state’s pristine night sky is actually darker than any other mainland US night sky because of Hawaii’s location along the equator. But light pollution in some places, especially Honolulu, has taken away the stars from the night sky.
“We’ve lost the opportunity to see the Milky Way on Oahu, probably forever,” Wainscoat said.
Though Wainscoat said Big Island nights are still darker than Oahu, he added that telescopes on Maunakea are particularly vulnerable to increases in brightness.
“If the night sky gets just 10% brighter… our telescopes will effectively get 10% smaller,” Wainscoat said, though he noted the sky over Maunakea summit hasn’t seen such an increase.
Sheldon Plentovich, an ecologist with the US Fish and Wildlife Service’s Hawaii and Pacific Islands program, said artificial lighting poses a threat to already endangered species like green sea turtles.
While the effects of artificial lighting on sea turtle hatchlings are well known — hatchlings attempting to crawl from their nesting sites into the sea can be easily disoriented by lights and led away from the water to die — Plentovich said the Pacific green sea turtles nest Sites are jointly threatened by light pollution and climate change.
As nesting sites in Hawaii are increasingly affected by light pollution, Plentovich said the darkest spots in the turtles’ territories lie largely in the French Frigate Shoals, which are themselves extremely threatened by climate change. She added that due to the effects of bright light on the behavior of turtles, seabirds, insects and more, it should be viewed as a form of habitat loss.
Graceson Ghen, Hawaii County manager for Hawaii Energy, said the Big Island has stricter lighting regulations to protect the night sky than neighboring islands, such as requiring all outdoor lighting to have less than 2% “blue light content.” The blue end of the visible light spectrum diffuses through the atmosphere more effectively than other parts of the spectrum and can appear brighter to the human eye.
Though the panel on Wednesday recommended no specific lighting policy changes at the county or state level, Ghen added that there are still ways residents and businesses can improve lighting to make nights darker, including using dimmable or shielded lighting that only illuminates key areas when people are there.
Wainscoat added that while there are numerous lighting violations that could result in a $500 fine on the Big Island, there is very little, if any, enforcement.
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