A new study from the Hawaiʻi Institute of Marine Biology at the University of Hawaiʻi at Mānoa is predicting most of Hanauma Bay’s beach will be underwater for a few days in 2030.
Researchers used models to show the impact of sea-level rise at the bay. They combined the lowest predicted rise of six inches with the island’s seasonal King Tides, when waves splash higher on the shore higher than normal.
It forecasts that 88% of the bay’s usable beach, or sandy portions, would be submerged in 2030.
“This is only during peak high tide to king tides that we experienced,” said Andrew Graham, a graduate assistant to the study.
“So it’s not going to be something that people have to worry about all the time. It’s just going to be a couple days a year, where the surf will come up to near the grass — which may increase crowding at the beach,” Graham said.
Kuʻulei Rodgers, the study’s lead researcher, said that six inches of sea-level rise can have a significant impact on the environment.
“This can equate to tens, even hundreds, of feet inland because you’re looking at the slope. So one meter of sea level rise vertically can equate to a lot more on the coastline,” Rodgers said.
The finding is part of a broader study that looks at the nature preserve’s ability to withstand damage from recreational, biological and physical uses — a concept known as carrying capacity. Researchers hope the study will help improve management and conservation efforts within the preserve.
The team has been conducting carrying capacity surveys at Hanauma Bay for the past five years…
Study: Rising sea levels will have dramatic effect on one of Hawaii’s most popular beaches
Nearly 90% of usable beach at Hanauma Bay could be underwater by 2030, according to UH study