Another heat record has potentially been broken. A buoy off South Florida has recorded ocean temperatures surpassing 100 degrees Fahrenheit, marking another milestone in the impacts of the climate crisis. 

A buoy in Manatee Bay, an area between South Florida and Key Largo, registered triple-digit temperatures over a roughly 3-hour time span Monday night. NOAA data shows that the buoy registered a temperature of 100 degrees Fahrenheit flat at 5 p.m. Monday, peaking at 101.1 degrees Fahrenheit an hour later and then remaining in between the two temperatures through 8 p.m. 

That temperature would have made the water as hot as a hot tub. According to the U.S. Consumer Product Safety Commission, hot tubs set between 100 and 102 degrees Fahrenheit are considered safe for most people. 

The buoy has not registered a temperature below 91.6 degrees Fahrenheit since that time on Monday. 

NOAA data shows that the Manatee Bay buoy in South Florida recorded triple-digit temperatures at 5 feet below the ocean’s surface, potentially breaking a world record for ocean sea surface temperatures. 

National Data Buoy Center/NOAA

Former NOAA hurricane scientist Jeff Masters tweeted Tuesday that the sea surface temperature recorded by the buoy was “astonishing.” That peak temperature, he said, was recorded at just five feet deep. 

If further confirmed, that temperature could mark a world record, he said. 

“Official world SST [sea surface temperature] records are not kept,” he said. “But according to a 2020 paper…the world SST record may be 37.6°C (99.7°F), recorded by the offshore station KISR01 in the middle of Kuwait Bay.” 

The study Masters referenced says the temperature recorded in Kuwait Bay at that time had never been previously recorded. That incident, the study says, was also “associated with heatwave, neap tides, and an extended period of Kous winds which are characterized by high humidity levels and accompanied by large-scale intermittent fish kill incidents that extended the full length of the Kuwait coastline.” 

There is a possibility that the Manatee Bay buoy’s record-holding status could be invalidated because the buoy is near land and the water may have organic matter that contributed to the temperature, Masters said. But even if it’s not a world record, he said it would still be a significant marker. 

“I have no doubt a dip in Manatee Bay today would have been a hot tub-like experience, with SSTs near 100ºF, and that these waters were some of the hottest ever recorded on Earth,” he said. 

Buoys nearby have consistently recorded water temperatures in at least the mid-90s for days now. The Little Blackwater buoy, located across a stretch of highway that separates it from the Manatee Bay monitor, hasn’t recorded temperatures below 91.4 degrees Fahrenheit since Monday afternoon. Further south, the Vaca Key buoy has also remained at temperatures in the low- to mid-90s. 

The sun rises over the Atlantic Ocean on July 13, 2023, in Miami Beach, Florida. 

Getty Images

How does extreme heat affect the ocean? 

The unprecedented temperatures hitting the waters off Florida’s coasts could be detrimental. Just a few days ago, researchers discovered that a coral reef restoration site off South Florida had “100% coral mortality.” When the ocean gets too warm, it causes the algae residing in coral tissues to be expelled, turning coral white instead of its usual vivid colors. It also leaves coral more vulnerable to disease and death. 

A loss of coral reefs also means a loss of marine life that depends on those systems for food and shelter. The United Nations Educational, Scientific and Cultural Organization has warned that more than half of the marine species in the world could face extinction by 2100 because of this issue. 

This photo provided by the University of Miami Coral Reef Futures Lab shows a bleached flower coral (Eusmilia fastigiata) on July 20, 2023, in the North Dry Rocks Reef off the coast of Key Largo, Florida.

Liv Williamson/University of Miami Rosenstiel School of Marine, Atmospheric, and Earth Science via AP

This could be particularly devastating in Florida, as the reefs play a major role in providing a barrier to hurricanes and also serve as a key economic source through the fishing industry and tourism. 

Warmer ocean temperatures can also make weather more extreme. Warm water evaporating can create clouds that eventually lead to storm systems. While the potentially record-breaking temperature in Florida was temporary, the current above-normal temperatures are part of ongoing unprecedented extremes hitting the planet as the impacts of climate change worsen. 

“We are in uncharted territory and we can expect more records to fall as El Niño develops further and these impacts will extend into 2024,” World Meteorological Organization director of climate services Christopher Hewitt said earlier this month. Around the same time, it was revealed that ocean temperatures worldwide have hit temperatures “much higher than anything the models predicted.”

“This is worrying news for the planet,” Hewitt said.