The video sheds light on the perilous condition of coral reefs amidst the record-breaking ocean heat wave in Florida, emphasizing the vital role these reefs play in the biodiversity of marine life and human livelihood. It foregrounds the urgent measures taken by conservationists and scientists to rescue and remove young corals to onshore nurseries to wait out the heat wave, highlighting the delicate balance and the process of coral bleaching.

The video further explains the biological mechanism behind coral bleaching, where warming seas disrupt the symbiotic relationship between corals and algae, leading to catastrophic effects if the situation persists. Scientists have developed new methods to speed up coral recovery and enhance resilience, such as through microfragmentation and propagation of heat-tolerant corals, standing as crucial responses to this environmental crisis.

Main takeaways from the video:

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Key Vocabularies and Common Phrases:

1. biodiverse [ˌbaɪoʊdaɪˈvɜrs] - (adjective) - Having a great variety of live forms or species in an ecological system. - Synonyms: (diverse, varied, multifaceted)

Coral reefs are one of the most productive and biodiverse ecosystems on the planet.

2. bleaching [ˈbliːtʃɪŋ] - (noun) - The process where corals lose their color due to stress factors like increased water temperature. - Synonyms: (whitening, fading, blanching)

When this happens, the coral expel the colorful algae in an attempt to save themselves. That's the process of bleaching.

3. symbiotic [ˌsɪmbaɪˈɑːtɪk] - (adjective) - Referring to a close, often long-term interaction between two different biological species. - Synonyms: (mutualistic, interdependent, cooperative)

Corals are animals, but in their tissues they have this symbiotic algae.

4. photosynthesis [ˌfoʊtoʊˈsɪnθɪsɪs] - (noun) - The process used by plants and other organisms to convert light energy into chemical energy. - Synonyms: (carbon fixation, photochemical reaction, chlorophyll action)

They use energy from the sun to create foods through photosynthesis.

5. genotype [ˈdʒiːnəˌtaɪp] - (noun) - The genetic constitution of an individual organism. - Synonyms: (genetic makeup, heredity, gene sequence)

We did that by actually removing individuals of all these different genotypes.

6. threshold [ˈθrɛʃhoʊld] - (noun) - The level or point at which something starts or changes. - Synonyms: (limit, boundary, verge)

Increasing heat has little impact until a threshold is crossed.

7. catastrophic [ˌkætəˈstrɒfɪk] - (adjective) - Involving or causing sudden great damage or suffering. - Synonyms: (disastrous, calamitous, devastating)

Then suddenly the results are catastrophic.

8. resilient [rɪˈzɪliənt] - (adjective) - Able to withstand or recover quickly from difficult conditions. - Synonyms: (durable, tough, flexible)

Each coral represents years of work towards creating a more resilient reef.

9. propagation [ˌprɑːpəˈɡeɪʃən] - (noun) - The action of increasing in numbers or spreading. - Synonyms: (multiplication, reproduction, dissemination)

By propagating the most heat tolerant coral, you speed up evolution.

10. anomaly [əˈnɒməli] - (noun) - Something that deviates from the standard, normal, or expected. - Synonyms: (abnormality, irregularity, oddity)

What we're seeing this year is very surprising and scary because we're seeing a three degrees celsius kind of temperature anomaly.

What is Coral Bleaching? The Fight to Save Coral Reefs | Weathered: Earth's Extremes

Coral reefs are one of the most productive and biodiverse ecosystems on the planet. Nearly a quarter of all marine species rely on them, as well as hundreds of millions of people that count on them for food, income and protection from extreme storms like hurricanes. But an ocean that's too hot by even just a couple degrees, could change everything. So I went to Florida to find out how close we are to crossing this threshold during a record breaking ocean heat wave.

I arrived while conservationists and scientists were carrying out the largest coral rescue attempt in history. All the teams in Florida kind of jumped into action to try to save as many corals as we can from the ocean. We did that by actually removing individuals of all these different genotypes, every single genetic individual that we had, and bringing them here. It's a desperate attempt to save as much biodiversity as possible, allowing corals to wait out the heat wave in onshore nurseries. Naturally growing coral can't be moved without damage. But young coral grown in labs and recently planted on ocean reefs can. So dozens of scientists and researchers carefully removed the young corals as water temperatures reached deadly levels.

Each coral represents years of work towards creating a more resilient reef. Corals are animals, but in their tissues they have this symbiotic algae. They use energy from the sun to create foods through photosynthesis. When the temperatures get too warm, let's say a little bit above 87 88 into the nineties, the algae actually stop being able to produce food for the corals and instead they produce toxic chemicals. When this happens, the coral expel the colorful algae in an attempt to save themselves. That's the process of bleaching.

Before this year, things were already pretty bleak. Unfortunately, it's estimated that about half of the world's corals had been lost already due to bleaching and other things. Like many other climate impacts, damage from bleaching is binary. Increasing heat has little impact until a threshold is crossed. Then suddenly the results are catastrophic. If they remain bleached for too long, they starve and die. It takes about eight weeks. Coral bleaching itself is nothing new. But what is new is how often these bleaching events occur, making it difficult for coral to recover in between. Too much bleaching, too close together and we lose the living corals, leading to the collapse of the reef structure where all of that biodiversity lives.

So scientists developed ways to speed up recovery and to improve resilience, which I'm going to see up close at Moat Marine Laboratory. And this process may hold an important clue to whether or not a coral tipping point has been reached. Jason. Hi, Maya. How are you doing? Very good. Show me around. Oh, come on. I'm so excited. This is staghorn coral. Coral nurseries like this are places where we can radically increase the number of new coral colonies. So we start with a piece of coral that we know is more resilient than average because it has already survived a heat wave.

What we're gonna do is we're gonna take this coral here and we're gonna fragment it into those micro fragments, working with our bandsaw. I don't know how accurate I'm gonna be. I'm gonna try my best. It'll be perfect. Look at that. Just a little dab. Just a little perfect. We're ready to glue them, get em off to their new home in the land based nurseries. When we do our microfragmentation process, we're trying to achieve a dinner plate size for those corals because that's about the rough size that the coral has to be to be sexually mature. Fragmenting the coral stimulates growth, shaving decades off the time it takes to reach maturity.

By propagating the most heat tolerant coral, you speed up evolution, and the reef can survive in warmer water. But here's the tipping point clue. Most of these strategies that we've been developing have shown a lot of promise in trying to buy corals, you know, one to two degrees celsius of heat tolerance. What we're seeing this year is very surprising and scary because we're seeing a three degrees celsius kind of temperature anomaly. Back in the 1960s and seventies, and even into the eighties, there was roughly 30% to 60% of the reef's surface was covered in living coral. Today, before this thermal event, two to 5% of our reef is covered in living coral.

Is that ahead? That's the spa buoy. The big deal I'm trying to... is this. Yeah, that's right. Wow. I didn't even realize that's what that was. That is crazy. I wonder how warm this water is down here. What I was looking at down here was bleached coral. You can see it's completely white. bleaching was everywhere. And this was the case for every reef that we went to. Fish were still using the features. But if the reef building coral have trouble recovering, the structure will eventually fall apart.

On the bottom, it was fluctuating between 91 and 92 degrees fahrenheit. And then at the surface, there was definitely. There were definitely a couple of spots where we hit 93. That is incredibly hot. Coral after coral after coral that are bleached. I would estimate something much greater than 90% of the corals down there. On this relatively high coral cover site, we're showing some signs of bleaching all the way through, completely bleached and then a much lower proportion are obviously already dead. So all of that bleaching is just over the last, over the last couple of weeks. But there's still some hope for these corals. If the temperatures drop back down quickly enough, they could survive.

Science, Environment, Climate Change, Marine Biology, Conservation, Global, Pbs