On land, in many parts of the world now, heat is shimmering off the pavement and forest fires are burning, so are the world's oceans.

More than 40% of the oceans are registering surface temperatures never seen in recorded history, and that figure is expected to pass 50% by September.

One weather buoy, in Florida's shallow and enclosed Manatee Bay, recently measured water temperatures at an astonishing 101 degrees Fahrenheit.

Riley Kaminer, an on-point listener from Miami, says it's not just a reading on a marine thermometer, you can feel the difference in the water.

I spent the day at the beach with my partner a couple weeks ago. The ocean is always a bit warmer in the summer, but for the first time this felt really quite different.

That temperature plus the rampant sargassum made for an uncomfortable beach day. I'm no climate scientist, but it seems to me that that doesn't bode very well for our planet.

Ted Furkins is the chief of interpretation and education at Florida's Biscayne National Park. He says Florida's fate cannot be separated from the fate of the waters that surround it.

So many livelihoods here in the state of Florida are based on the ocean in one way or another. That could be that they're in commercial fishing.

That could be that they're in the restaurant industry and that they serve fresh Florida seafood. There is a huge recreational fishing industry here.

There's a very big boat industry and boat manufacturers and the sale of boats has really risen in the last couple of years.

We've got big ports that have billions of dollars, worth of goods and merchandise coming through each year. We've got a big cruise industry that departs from Florida, that brings in lots and lots of visitors.

We've got these amazing beaches where people plan their vacations to come to. So just so much as the Florida economy is based on our proximity to the ocean and use of the ocean.

Furkins also says where he works, Biscayne National Park is home to some of the most famous sea-based residents in all of Florida. It's coral reefs.

Biscayne National Park is 173,000 acres. 95% of that is ocean. So we do have some of the northernmost Florida keys as landmass and we do have some of the short line.

But the vast majority of the acreage of Biscayne National Park is the ocean. We've got the Florida Keys coral reef track, which is the third largest living reef in the world.

And it runs about 350 miles along part of the east coast of Florida and down the Florida Keys. You know, I would add that to another part of our economy, the Florida Keys, like to call themselves the dive capital of the United States for people that come down and and dive the wrecks and the reefs here.

Well, listener, many Gilbert called us to sound the alarm about those same reefs. I live in the middle of the Florida Keys. I've been a resident there for over 30 years and I've never seen the water colors changed into a pea green as I have this last year.

And now with the high temperatures of the water, I can just look out in the water and see the coral turning pink and then white.

We have a serious, beyond serious issue now with this global warming.

As with any surprising environmental event, there's always debate. Are the measurements wrong? Is this an outlier year? Or is it another data point in the trend towards a hotter, less hospitable planet?

Well, listener Brian in Fort Lauderdale believes there's no reason to worry.

We recorded a hundred degree surface temperature, but if you go down maybe one foot or more, you're going to see normal temperatures throughout the coast of Florida.

...