Study Links Sea Level Rise and Maui Beach Erosion

Maui, Hawaiʻi.  File photo by Wendy Osher.

By Wendy Osher

Sea-level rise has been identified as a principal cause of coastal erosion in Hawaiʻi, according to a study released this week by the University of Hawaiʻi.

The study notes that Maui beaches are eroding at 13cm per year, with 78% of beaches on the island’s beaches showing erosion over the past century.

Maui’s erosion rate of 78% is well above the 52% rate reported on Oʻahu, where the average shoreline change rate was 3cm of erosion per year, according to findings released by the University of Hawaiʻi at Mānoa’s School of Ocean and Earth Science and Technology.

The findings were reportedly published in a paper produced by researchers from UH and the state Department of Land and Natural Resources.

In a press release issued by the university, officials say the study provides confirmation that, “future sea-level rise is a major concern for decision-makers charged with managing beaches.”

“It is common knowledge among coastal scientists that sea-level rise leads to shoreline recession,” said UH Sea Grant coastal geologist, Dr. Brad Romine, in a press release. “Shorelines find an equilibrium position that is a balance between sediment availability and rising ocean levels,” saying the findings confirm the importance of sea-level rise as a primary driver of shoreline change on both a regional and island-wide basis.

DLNR administrator Sam Lemmo also commented, “The research being conducted by SOEST provides us with an opportunity to anticipate [sea-level rise] effects on coastal areas, including Hawaii’s world famous beaches, coastal communities and infrastructure.”