US: Ocean temperatures hit hot-tub levels around South Florida

The surface ocean temperature in and around the Florida Keys soared to typical hot tub levels this week, amid recent warnings from global weather monitors about the dangerous impact of warming waters on ecosystems and extreme weather events.

A water temperature buoy located inside the Everglades National Park in the waters of Manatee Bay hit a high of 38.44ºC late Monday afternoon, U.S. government data showed, while other buoys nearby topped 38CºC and the upper 90s (32ºC).

Normal water temperatures for the area this time of year should be between 23ºC and 31ºC, according to the National Oceanic and Atmospheric Administration (Noaa), which published the findings from the National Data Buoy Center.

The readings add to previous warnings over Florida's warming waters in the southeastern United States as prolonged heat continued to bake other parts of the country.

The growing frequency and intensity of severe weather – both on land and in oceans – is symptomatic of global, human-driven climate change that is fueling extremes, experts in the field say, with current heatwaves expected to persist through August.

Earlier this month, the United Nations' World Meteorological Organization (WMO) said global sea temperatures have reached monthly record highs since May, also driven in part by an El Nino event.

The WMO and Noaa say temperatures like those in South Florida can be deadly for marine life and threaten ocean ecosystems. That can also impact human food supplies and livelihoods for those whose work is tied to the water.

As he worked his knife to filet fish hauled into Key Largo on Tuesday, fishing boat captain Dustin Hansel said the catch has been getting "slower and slower" for the past five summers. He's also been seeing more dead fish in waters around Key Largo.

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