A MARTÍNEZ, HOST:
An ocean heat wave off Florida's coast is breaking records for water temperatures. Now, the El Nino weather pattern is partly to blame, but scientists say what's really supercharging the heat is climate change. Jenny Staletovich joins us from member station WLRN in Miami, where she's been following this closely. Jenny, Florida summers - always hot and humid. What would it feel like, though, if we jumped in the ocean this week?
JENNY STALETOVICH, BYLINE: Yeah. Well, so usually in the summer, it can feel like climbing into a bathtub here, but right now it's more like a hot tub. Water temperatures typically average about 88 degrees in the summer. Now they're about five degrees higher. Water just offshore in Florida Bay near the Upper Keys hit 98 degrees last week. So that is literally hot-tub hot.
MARTÍNEZ: How unusual is that?
STALETOVICH: The heat we're seeing now is really unprecedented. Even climate scientists say they were caught off guard by such a big spike. Ben Kirtman is an atmospheric scientist at the University of Miami Rosenstiel School. And here's how he describes this ocean heat wave.
BEN KIRTMAN: It's bonkers. I don't know how else to put it. It's out of bounds from what we've seen. If you just wrote a statistical model and said what are the chances of this level of warming, it would be 1 in 250,000 years that that would happen.
STALETOVICH: So Kirtman says we normally break temperature records by fractions, like a tenth of a degree, not five whole degrees.
MARTÍNEZ: And warmer water can't be good news for ocean life.
STALETOVICH: No. So coral is probably the most immediate concern because reefs off Florida and around the Caribbean and the Bahamas are already in trouble. Since the 1970s, the reefs have lost about 80% of their coral. Now with such high temperatures this early in the summer, scientists are worried about widespread bleaching. That's when coral expel the algae they need to survive, and they die. Andrew Baker is a coral scientist at the University of Miami. He says corals have already started bleaching in Belize and elsewhere.
ANDREW BAKER: It's not as if it's just warming up here in Florida. This is clearly kind of a Caribbean regionwide thing. And that's, I think, why people are starting to think that it probably has some legs and is likely to be with us for a while.
STALETOVICH: And summertime is also when corals spawn. So in the next two weeks or so, Baker says scientists will decide if they want to remove some corals from the reef and let them spawn in labs. Then they'd release the babies back into the ocean.
MARTÍNEZ: What about sea critters? How are they doing?
STALETOVICH: So water sucks up a lot of oxygen, which can lead to fish kills. We saw some rare fish kills off Miami three years ago. And a hotter ocean could also lead to warmer trade winds, which help cool Florida. So that could exacerbate the record heat that we're already feeling on land.
MARTÍNEZ: And how does this look for hurricane season?
STALETOVICH: So this season was supposed to be the first near-normal season after seven above-average seasons because of that El Nino weather pattern, which can weaken storms. But some forecasters are already adjusting their predictions. They think all the hot water, which can fuel hurricanes, will cancel out the effects of the El Nino.
MARTÍNEZ: Man. OK, so any relief in sight?
STALETOVICH: So ironically, hurricanes could provide some temporary relief. They suck up heat and mix deeper cooler waters with hot surface waters. But atmospheric scientist Ben Kirtman says that what we've seen from climate change so far is that ocean temperatures can ratchet up and then plateau. But he says they never really go back down.
MARTÍNEZ: Jenny Staletovich with WLRN in Miami. Thanks a lot.
STALETOVICH: You're welcome. Transcript provided by NPR, Copyright NPR.
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