The Oceans Are Getting Hotter—And Greener

11:52 minutes

Aerial view of Mauritius island panorama and famous Le Morne Brabant mountain, beautiful blue lagoon and underwater waterfall.
The ocean has been changing to be more green in recent years. Credit: Shutterstock

It’s hot out there, and more so than normal July weather. It’s estimated that more than 100 million Americans are under heat watches, warnings, and advisories, spanning the west coast and southern states. Not only is the land hot, but the oceans are, too. The water temperature near the Florida Keys this week reached 96.8 degrees Fahrenheit, just shy of the record for global ocean temperature.

A warmer climate is having some visual effects on our oceans, too. The color of the ocean surface near the equator has gotten greener. The culprit? Phytoplankton, which are full of the pigment chlorophyll. 

Joining Ira to talk about these stories and other science news of the week is Rachel Feltman, Editor at Large for Popular Science and host of the podcast “The Weirdest Thing I Learned This Week,” based in Jersey City, New Jersey.

Segment Transcript

IRA FLATOW: It is hot out there and more so than normal July weather. It’s estimated that more than 100 million Americans are under heat watches, warnings, and advisories spanning the West Coast and South. And it’s not just the land that’s hot. It’s the ocean, too.

Here with me to talk about this hot story and other science news of the week is Rachel Feltman, editor-at-large at Popular Science and host of the podcast The Weirdest Thing I Learned This Week. Rachel is based in Jersey City, New Jersey. Welcome back to Science Friday.

RACHEL FELTMAN: Thanks for having me, Ira.

IRA FLATOW: Nice to have you. OK. I can tell it’s hot by just walking outside my house. But that’s just my little corner of the world. Right? How hot has it– just how hot has it been?

RACHEL FELTMAN: Yeah. Too hot is the answer. Last week, we broke several world temperature records in a row. The news is just out that June was officially the hottest June ever on record. So things are superlatively hot. And I would rather they were not but that is the case.

IRA FLATOW: Yeah. You know, I’m looking at the water temperatures off the coast of Florida and they’re insane.

RACHEL FELTMAN: Yeah. So basically, all around Florida the water is abnormally hot but especially around the keys near Everglades National Park, the temperatures hit 96.8 degrees Fahrenheit on Monday, which is 10 degrees Fahrenheit higher than the average summer peak. And it’s just shy of the global ocean temperature record, which was set in Kuwait in 2020. And these are like sustained temperatures.

Of course, El Niño involves warmer oceans. And we knew that that climate pattern was coming up. We knew to expect this. Scientists have been saying for years climate change is happening and the next time we have one of these sort of natural peaks in heat, it’s going to be really bad. And sure enough things, are pretty dire.

IRA FLATOW: Yeah. It looks like Florida is conducting its own boiling frog experiment.

RACHEL FELTMAN: Oh yeah. Yikes.

IRA FLATOW: And you know, I joke about that but it’s actually very bad for the sea life there, isn’t it?

RACHEL FELTMAN: Yeah so one thing that scientists are really certain of is that this heat in the water is going to cause a lot of coral bleaching. And of course, that’s dangerous not just for the coral themselves as living organisms but the many, many organisms that live on or connected to that reef ecosystem. And reefs, of course, also help protect the land during storms like hurricanes. So it’s bad news all around.

IRA FLATOW: Speaking of storms, we’re barely into the summer and who knows what the hurricane season is going to be like considering all this hot water around there.

RACHEL FELTMAN: Yeah. It’s interesting because El Niño tends to favor stronger hurricane activity in the central and Eastern Pacific but actually lower hurricane activity in the Atlantic but warm water does fuel hurricanes so now we’re in this interesting position of being like is the water so warm that we won’t see that usual downturn in activity that we expect with El Niño. So that’s something that we’ll just have to wait and see as the season unfolds.

IRA FLATOW: Yeah this might be what the new abnormal looks like with climate change. Our next story is also about climate change and the oceans but about oceans changing colors.

RACHEL FELTMAN: Yeah. So based on satellite observations, over the last 20 years, more than 56% of the world’s oceans have changed color to an extent that can’t be explained by natural variability so climate change is the likely culprit.

IRA FLATOW: Well, what kind of colors are we talking about here? Rainbow colors?

RACHEL FELTMAN: Fortunately, no. A rainbow ocean sounds nice in theory but would probably be pretty freaky. The greening of the oceans is what we’re mostly talking about. The color of the ocean comes from what’s hanging out in its upper layers. So when you see a really deep blue sea, there’s actually very little life in there. And green means there’s phytoplankton, the stuff eating the phytoplankton. And so yeah, that’s normal. It’s good for there to be food for the fish. But there’s a balance so it’s not necessarily good that we’re seeing these big changes in the ocean ecosystem.

IRA FLATOW: And we don’t know whether it could be permanent yet, do we?

RACHEL FELTMAN: No. This is all very preliminary. Basically, it’s just like we can confirm the shift is happening and that we can’t explain it with something other than climate change.

IRA FLATOW: All right. While we’re on the subject of algae, let’s talk about something that’s totally different. And this one could seriously cut down greenhouse gas emissions from cow poop. Algae and cow poop. You’ve got to connect those dots for me.

RACHEL FELTMAN: Yeah. So there have been a few studies over the years about adding this species of red algae to cattle feed because, basically, as many people know, cows produce a lot of methane in their burps. And this is a huge contributor to greenhouse gases in the dairy and the beef industry. And it’s all due to the magical, wonderful stuff that happens in their four-chambered stomachs.

And when you add certain things to that mix, it can kind of change the chemical equation and make less methane come out. So there’s been some research on feeding cows some stuff like this algae to make them burp less methane. But there are some concerns with that. It’s like is it really safe to feed them a bunch of algae.

All of that is still very much in progress. And these researchers decided, you know what if we address this other slightly smaller source of methane emissions, which is just the stored manure. Like all that cow poop has to go somewhere and where it sits in storage, it releases methane. And they found that when they just like, basically, just pour the algae on the poop and it did cut down on the methane emissions by I want to say about 44%.

IRA FLATOW: Wow. We’ve talked on this show before as you say about feeding cows the algae. But this addresses the issues on the rear end side of things. The back end, so to speak.

RACHEL FELTMAN: Yeah. Unfortunately, that poop problem only accounts for about 12% of the total methane emissions from the cattle industry. So it’s a good problem to solve but, unfortunately, it will not give us carbon neutral beef.

IRA FLATOW: Yeah. OK. Let’s move from the deep in the ground on Earth here to Mars. There’s more evidence for water on the red planet?

RACHEL FELTMAN: Yeah. Basically, Perseverance has been poking around this area called the Jezero Crater. It was there a while back. And new research on some of the samples it analyzed while it was there in those rock formations shows a bunch of signs of organic molecules. And organic molecules are basically the building blocks of life.

They don’t necessarily and almost certainly in this case don’t mean that life was present but it’s the kind of like chemical processes that happen in rock and water that create an environment where life can evolve, like it did early on on Earth, so always exciting to see signs that Mars was once perhaps wet and full of the same sort of just chemical shenanigans as happened a long time ago on Earth.

IRA FLATOW: Let’s move on and talk about two important FDA approvals that are making the news this week. The first one we’re talking about is the first over-the-counter birth control pill. Big deal this is.

RACHEL FELTMAN: Yeah. A really big deal. A bunch of companies and advocacy groups have been working toward this for a long time. And this is the first oral contraceptive pill that is going to be available over the counter, hopefully sometime in 2024. But it’s a big deal that the FDA has cleared this. And hopefully, it’s just the first of many.

IRA FLATOW: Is this different from the birth control pills that have been available with a prescription?

RACHEL FELTMAN: So what’s exciting is that it really isn’t it is, of course, just one type of pill. It’s a progestin only pill. And there are many other types of oral hormonal contraceptive. But what’s cool is that this is basically just that a company has demonstrated and the FDA has verified that this pill is safe and effective enough for it to be sold over the counter. So hopefully, some other types will be approved, too.

IRA FLATOW: And the other FDA approval this week is for a colonoscopy prep that tastes like a sports drink. Boy, people will be happy to hear that.

AUDIENCE: Yeah. So they say. I certainly hope it lives up to the hype. But yeah, Souflave is a new oral prep solution that is supposedly both low volume, and very effective, and tastes like a lemon lime sports drink. And that’s a really big deal because there is very low compliance. Something like 72% of people are up to date on their colonoscopy screenings.

And especially with the rise of colorectal cancer in especially young people, it’s just really important to get people to those screenings. And studies show consistently that one of the biggest hurdles is that people hate the solution prep because it’s so gross. So I’m really glad to see that the pharmaceutical industry is working on tackling that problem because it might sound kind of superficial but it could really make a difference in getting people screened.

IRA FLATOW: Yeah. Let’s finish off with a story about the ingenuity of birds. We’ve been hearing about right how ingenious, they make and use tools. And now some birds have managed to keep other birds away from their nests by stealing anti-bird– those little pointy things from buildings.

RACHEL FELTMAN: Yeah. I really love this story because the birds have just really showed us up. Yeah. Researchers in Rotterdam in the Netherlands found that some crows were making their nests using those long spikes that get attached to buildings to keep birds away. And the crows were using them as like structural material.

But then once they started looking, they found that magpies which build these really large dome nests, they were actually using them for their intended purposes. They used the spikes on the outside of these giant domes to keep other birds from landing on their nests. They look awesome. I definitely recommend that people look up the photos. And it just goes to show you that the birds have it all figured out. And we’re just along for the ride.

IRA FLATOW: Well, yeah, we are. And it’s actually a good example, I think, of how birds are adapting to urban environments like we do when we move into town.

RACHEL FELTMAN: Yeah, absolutely. And recently there was another study that was like about how all of these bird species are building nests with potentially dangerous trash, like cigarette butts and plastic bags. And that obviously is a huge bummer and a reminder to people to try to produce less waste and definitely control your litter. But I love that there is this more optimistic, uplifting story of birds using human junk to make their lives better.

IRA FLATOW: Always another wonderful thing to talk over a beer tonight on Friday nights. Thank you, Rachel. Always great to have you.

AUDIENCE: Thank you, Ira. Rachel Feltman, editor-at-large for Popular Science and host of the podcast The Weirdest Thing I Learned This Week. Rachel is based in Jersey City, New Jersey.

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About Kathleen Davis

Kathleen Davis is a producer at Science Friday, which means she spends the week brainstorming, researching, and writing, typically in that order. She’s a big fan of stories related to strange animal facts and dystopian technology.

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Ira Flatow is the host and executive producer of Science FridayHis green thumb has revived many an office plant at death’s door.

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