Hawaii is expected to experience coral bleaching a third year in a row, as the globe is experiencing the most widespread coral bleaching event on record, scientists said Monday at the 13th International Coral Reef Symposium in Honolulu.

“For Hawaii and Florida we are looking at the potential of three years in a row of coral bleaching,” said Mark Eakin, coordinator of the National Oceanic and Atmospheric Administration’s Coral Reef Watch program. “At this point the global coral bleaching event that is going on is already the longest we have ever had and doesn’t show any sign of stopping soon.”

Eakin, along with other scientists from NOAA, presented findings at the symposium, which is being held at the Hawai‘i Convention Center through Friday. At the event, which takes place every four years, academics and policymakers gather to share research and technologies regarding coral reefs worldwide.

More than 2,500 people from 97 nations registered to attend. They include coral reef scientists, conservation managers, educators, three country presidents, policymakers and students. Organizers said this year’s symposium is the largest to date.

This is the first time Hawaii is hosting the six-day event, which features nearly 90 sessions with topics ranging from coral bleaching and fish ecology to the latest technology in studying reefs. It’s anticipated to generate $9.4 million for the state economy.

Tickets to the symposium are $880 for those who are not members of the International Society for Reef Studies.

The total economic value of the Hawaiian Islands’ coral reefs is $33.57 billion, according to a survey conducted by NOAA in 2009. The value was based on a survey of U.S. households, asking respondents how much they are willing to pay to protect the coral reef ecosystem for future generations, as well as a calculation of the value of direct use of coral reefs for snorkeling and fishing.

Eakin said that when the coral bleaching event began in 2014, the impact was especially damaging around Oahu, and in 2015 the severe bleaching spread across the islands.

“Oceans are crucial to our way of life in the islands,” said Marti Townsend, executive director of the Sierra Club of Hawai‘i. “We must do all that we can to ensure they are healthy. If another year of coral bleaching events is expected, then we know we are not doing enough to stem the effects of climate change.”

NOAA said global warming combined with El Nino has made the third coral bleaching event the longest on record. When water is too warm, corals will eject the algae living in their tissues, causing the coral to turn completely white. Coral does not die when it bleaches, but could, as the coral is under more stress.

Eakin said the repeated stress of bleaching will lead to more coral dying.

“More corals are likely to die when they bleach in the subsequent years,” he said.

Eakin said that the coral bleaching occurring worldwide is now the most widespread it’s ever been, as over half of the areas that have already experienced coral bleaching have been hit twice.

“The most threatened areas right now are Micronesia and Palau,” he said. “The model is showing that there is a potential for severe bleaching for several months from now until the end of the year.”

The presidents of Palau, the Federated States of Micronesia and the Republic of the Marshall Islands are attending the symposium. Palau President Tommy Remengesau was the keynote speaker Monday.

In October, Remengesau created the Palau National Marine Sanctuary, which covers all of the nation’s waters — more than 37o,000 miles — and includes an 80 percent no-take reserve and a 20 percent protected domestic fishing zone.