Updated August 13, 2023 at 9:15 AM ET
As Lindsay Beriault dove into the waters of Florida Keys, she was eager to adore the ocean's coral reef. When she opened her eyes, her emotions shifted from wonder to sorrow and grief.
"As soon as I got in the water and over to the reef, I immediately started crying," Beriault said. "My mask was flooded with tears, not ocean water. It was devastating."
The Florida Keys coral reef, once lively shades of green, brown and yellow, were completely stone white.
The vibrant hues of the reef have been muted by a natural process called coral bleaching. Climate change is the leading cause of coral bleaching. When water temperatures are too warm, corals expel algae from their tissue, which cause them to turn white.
Beriault, who is a tour guide at John Pennekamp Coral Reef State Park, could hardly handle the warm water that the coral reef lives in.
"You're always looking for that refreshing cut off from the hot air. But when you jump in, you're almost like jumping into a hot tub," Beriault said.
What experts say about Florida's coral condition
Bleached corals have a chance to revive if water temperatures cool, according to Jennifer Pollom, executive director of the Ocean Conversation Foundation. But that's unlikely in consistent triple-digit heat.
In late July, water temperatures in Manatee Bay reached 101.1 degrees Fahrenheit. Triple digit numbers pose a major threat to Florida's coral reef and the life around it.
"The bigger impact is that tourism economies like Key Largo, where we're located, are dependent almost entirely on the reef and the marine ecosystems," Pollom said.
Florida's coral reef is basically extinct. Only 2% of the natural reef remains.
"We believe that the reef can't come back without human intervention at this point," Pollom said. "But there's a lot of hope."
Florida is undergoing a massive effort to outgrow the reef.
Sarah Fangman, a marine scientist and superintendent of Florida Keys National Marine Sanctuary, is a part of that effort. She oversees a federally funded mission to restore the state's coral reef. Their efforts include growing and transplanting corals along the Florida Keys. But warmer temperatures are an inevitable and uncontrollable factor.
"Corals are like Goldilocks. They like the temperature to be just right, not too hot, not too cold. Right now, it is undeniably too hot," Fangman said.
To Fangman, marine life is like human life.
"I do not have a way to turn down the temperature and the thermometer of our ocean," she said. "But what we can do is address other threats so that these corals and the ecosystem are more resilient."
Planning a trip to the Florida Keys? Here's what to know before you go
First, "look before you book," Fangman said.
She recommends tourists research eco-friendly activities.
Next, choose a reef safe sunscreen.
"Reef safe sunscreen is probably one of the best things people could do if they plan on getting in the water," Beriault said.
She warns to stay away from mainstream brands that are only labeled 'reef safe,' and opt for a mineral based sunscreen instead.
"To be reef safe is mineral based sunscreen, which means it contains zinc oxide or titanium dioxide," Beriault said. "Corals take in nutrients from the water. If people are wearing harsh chemicals found in common brands, it kills corals just as high temperature does."
Finally, see something? Say something.
Report coral bleaching to local restoration programs.
"We need to know where the places are that are particularly vulnerable, but we only have so many scientists," Fangman said. "While you're out snorkeling, diving, enjoying these waters, you can help us by reporting what you're seeing."
Treye Green edited the digital version of this story. contributed to this story
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