Coral reefs suffering from climate change: scientists warn we’ve crossed a tipping point

0:00 What if the world's coral reefs are no longer a future crisis? Like we're not predicting this anymore, but a crisis is already underway. A new global report warns that we've passed the first major climate tipping point and the way we thought about gradual change may already be too late. I remember diving in like beautiful spots in the Caribbean. Grant came in, is one of the spots that I remember just profusely. It's just amazing way to go down and enjoy a coral reef that hasn't been touched by anything. But then I've also gone diving on a lot of sites that have been touched by climate change. Rapid increases in temperature. Throw off the corals. They bleach for too long, and they end up being ruined and the entire habitat's ruined.

0:41 The fish are gone. There's nothing for that area, not just to scuba dive, but to fish on, or even just to provide protection for the coastline. We're gonna talk about this new tipping point, how it's already underway, and the time for prediction is over on this episode of the How to Protect the Ocean Podcast. Let's start the show. Hey everybody. Welcome back to another exciting episode of the How to Protect the Ocean Podcast. I'm your host, Andrew Lewin, and this is the podcast where you find out what's happening with the ocean, how you can speak up for the ocean, and what you can do to live for a better ocean by taking action. On today's episode, we're gonna be talking about what's happening in the ocean. Unfortunately. It's not good news. There was a report that came out that I actually saw on The Guardians, an article on The Guardian that talked about this report, that talked about tipping points and how coral reefs have already hit the first tipping point.

1:29 Now, a tipping point is essentially a point in which these coral reefs or habitat or something in the wild has gone past where there's really no going back. Right? That tipping point is where, you know, you look at something that like a bottle of liquid and when you tip it over, you lose more and more liquid. But at some point you're gonna tip it so much that you're gonna lose most of that liquid. That's the tipping point that we're kind of talking about here. But in this case, we're talking about coral reef health and what we've seen over the time, like in the past few decades is the prediction of hearing that coral reefs are going to be lost on a regular basis. We're gonna see that coral reefs in certain areas, whether it be remote or on the coastline are gonna be lost for a long time, if not forever, or we're going to see a shift in that change of species makeup because it can only handle a specific tolerance of environmental factors.

2:17 So let's just talk about coral reefs for a second. They are an animal. They have a very narrow tolerance for different environmental factors such as temperature, pH and just salinity in general. If you've ever had a marine aquarium at home like I have in the past, you will know that when you put a coral reef in the tank, it is very sensitive to change. So when you have a smaller tank, especially when you compare it to the ocean, any change in water quality, like a dip in salinity, or an increase in salinity, or a dip in temperature, or an increase in temperature, or a dip in pH, or an increase in pH, if it's this out of whack within that narrow range in any of those, or all of those will kill the corals. They will die if it's prolonged. And so I was explaining this to a friend of mine at work today who was asking about coral reef health, and he was like, what happens when coral reefs die?

3:04 And essentially when sea surface temperature related, or there's something that is not good. That's happening in the ocean, right where the zoo the little phytoplankton that live in the corals, they start to get excited. They don't like what's happening in there. It's either too hot or something's gone wrong. The pH is off, something's gone wrong. They get ad, they get expunged. Actually, the coral reef skeletons like, you gotta get outta here. And when that phytoplankton leave the coral skeleton. It is just a skeleton. The phytoplankton provide the color and provide the ability for it to be fleshy kind of thing. Like that flesh that you see on a coral, the softer part of the coral around a hard coral. If you think about like a branching coral, there's a little bit of a flesh around it, like a little polyps that come out. That's the fleshy part.

3:44 That will eventually die. And then you'll just have a coral skeleton, which is basically a rock, like it's made of limestone and will eventually degrade over time. If there's the environmental factors there, like say high sea temperature, if that's there for a prolonged amount of time, so more than like four or five days, six, seven days, the phytoplankton won't come back, but if it does go back to the regular range, you also get new phytoplankton in. There's an ability for this coral to recover and become healthy once again. So we've seen that over time. The Great Barrier Reef is a great example. 93% of the barrier Reef a couple years ago bleach. But then most of that came back because it wasn't a prolonged event. It wasn't a prolonged like high sea surface temperature event where we saw bleaching for a long, long time. It was just in short spurts. Still not great, still not healthy for the coral, but it allowed it to recover in most places.

4:29 This happens all over the world. Now we're starting to get to points where this tip, like the tipping point, we're starting to get to points where they're not gonna recover because the amount of days where the temperature is high is elongated just it lasts for a longer time. And so when we see that, we start to see the corals bleach for longer and then they start to die off. Now these are areas like the great barrier reef, where we've got areas along the coastline where people fish, they provide security for wave action against wave action. When you see like tsunamis or even high sea like sea waves come through. They provide all that safety because when the wave energy goes over the corals, because the corals are kind of like interjecting and getting in the way of the wave, the energy dissipates as it gets closer to the shore. It's not as if it's gonna be like perfect, it'll just dissipate down to normal, but it will take away some of that energy so you don't get as much of a storm surge.

5:17 Or in the case of a tsunami, you'll get less of a surge coming at the beach. And that's an important part when we talk about security of a coastline from erosion or even just, you know, absolute chaos when it comes to a tsunami. So that's what we're talking about when we talk about tipping points and how things happen. You know, gradual impacts will happen. But if it continues to happen and it continues to happen, we have a problem. There was a point where remote reefs that weren't in contact, constant contact with humans, they were fine. They would bleach, but then they would come back because there was nothing else that was cumulative. So there nothing else that was in its way, like wasn't bad water quality, wasn't people diving on it all the time and like messing it up or fishing all the time and like putting anchors along the coral reef.

5:57 Nothing was disturbing it, but in areas where they're along the coast where we had bad water quality coastal development that caused sedimentation, that like would just basically smother the corals, there would be like nutrients in there. So a lot of algae would grow over the corals. All these little things didn't help. And then you have climate change come through. They didn't have a chance. So a lot of these corals, if they have a lot of cumulative impacts plus climate change, we have a big problem. But now just climate change is causing a problem for a lot of these remote reefs. And that's a big problem. That's a huge problem. There's no more scuba diving on, no more, snorkeling 'cause there's nothing to see. The fish are gone, the turtles will be gone, the sharks will be gone. You know, invertebrates will be gone because there's nothing there to hide. These coastal systems, these coral reefs provide areas where you can hide as a fish, as an vertebrate, so you can't get caught.

6:41 And there's a lot of food in there as well for specific species and stuff. It's really, really a diverse system that is stable and that's what we want. Right. But here now we're talking about this report that came out, it says Coral reefs have crossed their tipping point threshold at about 1.2 degrees Celsius of warming above normal. Mass die off and decline are inevitable in most reef systems. So we're expecting a lot of these reef systems to just start to decline. Current global warming, is already at 1.4 degrees Celsius, and it's predicted to go up to three degrees Celsius above what is considered quote unquote normal for certain areas. Now, the future warming predictions without radical emissions cuts the 1.5 degrees Celsius is likely within probably the decade and worsening the collapse.

7:24 Now, the broader earth system risks like ice sheets, Amazon, rainforest, and Atlantic circulation are closer to tipping than scientists previously thought. Now these used to be like way out predictions. It's gonna happen in like a hundred years. It's gonna happen in like 200 years and stuff like that. Now the predictions are coming even closer because we've already hit these tipping points and this is gonna be a cascading effect. Now, of course, once one system collapses like reefs, you know, death, reducing carbon storage can accelerate other stressors. Like even when we talk about forest fires, right? and the fact that we have wildfires. As these trees burn up, all the carbon that they used to store would go into the atmosphere. It's the same thing with coral reefs. All the carbon that they stored in the rocks, in the corals would go up into the ocean, into the atmosphere, making things worse.

8:06 Some experts note that there is uncertainty. So coral refuges and cooler or deeper waters may actually persist. Local management that manages pollution and overfishing still actually matters. So the fact that you can take away cumulative effects from human effects, that's a huge thing. That's a very big plus and allows the coral reef systems to be a little bit more resilient in the face of climate change. Not to say that climate change won't affect them periodically, but it may not affect them on a permanent basis in certain areas. Now, of course, not all scientists agree on the precise thresholds. Reef resilience may vary from region to region and from species to species. I remember reading studies that have different types of phytoplankton within the corals, so they call 'em A, B, C, and D. The D type had a larger range of temperature threshold, so that means it could handle a lot more of a higher range of temperature.

8:54 These zoo, these phytoplankton that are in the corals, if it's a higher temperature, they can actually stay in for longer, but it's only in specific species. reeses, we know it could change in the makeup that they have that may not be more branching corals or harder corals might be more soft corals. So that might be a change that we might see. Now, of course, some ecosystems show recovery potential if local stressors are managed, which I talked about already. These create tensions between like the Domus narratives, it's over, and the resilience narratives. There's still hope. So I never wanna say that our coral reefs are beyond repair. What I'm saying is that we're gonna see a change in coral reefs if we don't make any changes. If we get back through like lower than the tipping point of the 1.2 degree Celsius or whatever that might be, then we are in better shape.

9:37 Unfortunately, the actions that we've taken as a human species hasn't even come close, and we're actually predicted to go to three degrees above normal. So that's gonna be a problem. So like some of the consequences that we're gonna see in cascading risks is like reef collapse, that which is reducing biodiversity. Affects keystone species that it could be good for fisheries, that could be good for stabilizing the ecosystems like sharks and so forth. And of course, destabilizes ocean food webs, as I just mentioned, without sharks or any other types of predators that actually are like apex predators for that food web. Now, of course, you know, reefs are dependent and people dependent on reefs. So 500 million people worldwide depend on reefs for food, income and coastal protection. Reef loss means that food insecurity, economic hardship and greater exposure to storms are gonna be get worse.

10:21 And that's not good. So the dying ecosystems release carbon when they die, and so they lose their capacity to absorb it, worsening climate change. So that's gonna cascade in a bad way, let's just say. But look, there is a path forward. There are a lot of paths forward, so the global actions like urgent emission reductions are the only way to halt the warming. That is really it. Anybody else can say like, we can do as much restoration for corals or sea grasses or anything like that, that will help in the meantime. But while we see this happen, we have to reduce urgently these emissions, like we have to cut them. It's has to happen. We're starting to see the emergence of renewable energy, which is great, but we're also starting to see that there's a lot of halting of that renewable energy or the construction of that renewable energy because of other fossil fuel favor I guess is really what it comes down to.

11:05 a lot of countries. So we're still having that push and pull, including my own, in Canada. We're still having that push and pull, which is not good for us. Now, local mans are reducing any kind of cumulative effects, so overfishing, pollution or destructive practices can help. The measures won't stop bleaching necessarily, but can help by reefs like some reefs, some time, which will be great. And restoration and innovation. So coral nurseries assisted evolution, which has just changed like looking at the makeup of how this is gonna change. Like, so some researchers are working on heat tolerances of coral reefs, and then of course large scale restoration, which is extremely expensive. Efforts offer potential, though not at a scale that will help the crisis. So there are some positive tipping points. So there's renewable energy growth, as I mentioned. There's following battery prices so we can store that renewable energy more.

11:48 And lifestyle changes can quickly reshape systems giving hope. So look within, look at home, start small and then act big. You know, they also say act local, you know, think global. That's what we need to do. Of course there is a huge role for science communicators and public voices, but they need to be listened to and we need to be really cognitive of how we portray this message. I don't want people to feel like, Hey, it's your fault. How dare you do this. If you ignore the problem, it's not gonna go away. No, I think there's a community aspect to it. It's like we wanna take care of our community, our local community, our regional community, our national community, you know, our international community. We wanna take care of each other. We wanna take care of this planet because we love nature, we love the ocean, and there's more to the planet than just earning money and destroying the planet.

12:33 There's more to that and we need to act on it right now. So while reefs are in crisis, the story isn't just about loss, it's about what we can choose to do now. Like I said, every personal action that you take locally in your household will work. Every time you vote, vote for somebody who's actually gonna vote for in favor of the environment of the ocean. Reduce climate change. Right. And advocacy steps like actually focus on looking at nonprofit organizations or organizations that are out there, or even individuals that are out there that are helping to support reducing climate change. They're helping to support the education of what we need to do to help our planet, what we need to do to reduce this tipping point or get back over, hopefully, that we can stop from getting further down the road and losing coral reef systems altogether in a longer term, which is not good.

13:19 Right? So the choices between like we can go cascading collapses, or we can go cascading solutions. Which one do you want? Let me know in the comments below. I'd love to hear if you're watching this on YouTube. Love to hear your opinion on this. Is it to doom and gloom? Or do you think that we have passed the tipping point and we need to get back into it? And you're ready to take some action? Let me know what action you're gonna take. Let me know the comments below. If you're watching this on YouTube, if you're listening to this on the audio on your favorite podcast app let me know what you think. DM me on Instagram at How to Protect the Ocean, or Go to speak up for blue.com/contact, fill out the form goes right to my email address and I will answer it as soon as I can. I wanna thank you so much for joining me on today's episode of the How to Protect the Ocean Podcast. I'm your host, Andrew Lewin from the True Nor Strong and Free.

14:00 Have a great day. We'll talk to you next time and happy conservation.