NOAA confirms 4th global coral bleaching event

[cozcharlie]

NOAA confirms 4th global coral bleaching event . This could probably be listed in 20 places on scubaboard , but clearly Cozumel was affected


The world is currently experiencing a global coral bleaching event, according to NOAA scientists. This is the fourth global event on record and the second in the last 10 years.

Bleaching-level heat stress, as remotely monitored and predicted by NOAA’s Coral Reef Watch (CRW), has been — and continues to be — extensive across the Atlantic, Pacific and Indian Ocean basins. CRW's heat-stress monitoring is based on sea surface temperature data, spanning 1985 to the present, from a blend of NOAA and partner satellites.

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[NOAA confirms 4th global coral bleaching event]

 

[WillieJustice]

Saw a bit of that earlier today at Palapas reef. Just a bit for now.

 

[mattfish]

This really is bad bad news. This year the global average temps are already way up over even last year. I fear that if summer 2024 is like summer 2023 the Caribbean is not going to withstand it

 

[NitroxSam]

I noticed sparsely populated reefs and quite a bit of bleached coral in Key Largo last September. Water was 88 degrees at most locations. We dove French, Elbow, Dry Rocks, Benwood, and Hannah M. Bell. The wrecks had more fish than the reefs. The dive operator told me that the higher water temps hit earlier than normal, so the elevated temps are lasting longer than usual. We didn't go to Molasses at all that week, which I have heard is still in good shape.

 

[cozcharlie]

I noticed sparsely populated reefs and quite a bit of bleached coral in Key Largo last September. Water was 88 degrees at most locations. We dove French, Elbow, Dry Rocks, Benwood, and Hannah M. Bell. The wrecks had more fish than the reefs. The dive operator told me that the higher water temps hit earlier than normal, so the elevated temps are lasting longer than usual. We didn't go to Molasses at all that week, which I have heard is still in good shape.

While the Keys had both occasional super high water temps AND a long duration event, I think it was primarily the long duration that caught Cozumel. I think annual high water temp was probably only a degree or two above normal highs when using reliable sources , what really hurt was that the water got hot early and stayed that way. Instead of reefs enduring a couple of months of high water temps they endured almost 6 months .
This year is shaking up to be real mess for hurricanes and everything else. Very high ocean heat content and low wind shear forecasts from La Niña. After putting our very high hurricane season forecasts, forecasters basically said all of their forecast model inputs pointed the same way —if this wasn’t a big hurricane year they may as well throw in the towel. Maybe Saharan dust will kick up help mitigate things for us (though they certainly will not mitigate my allergies )

 

[Sloeber]

While the Keys had both occasional super high water temps AND a long duration event, I think it was primarily the long duration that caught Cozumel. I think annual high water temp was probably only a degree or two above normal highs when using reliable sources , what really hurt was that the water got hot early and stayed that way. Instead of reefs enduring a couple of months of high water temps they endured almost 6 months .
This year is shaking up to be real mess for hurricanes and everything else. Very high ocean heat content and low wind shear forecasts from La Niña. After putting our very high hurricane season forecasts, forecasters basically said all of their forecast model inputs pointed the same way —if this wasn’t a big hurricane year they may as well throw in the towel. Maybe Saharan dust will kick up help mitigate things for us (though they certainly will not mitigate my allergies )

For Cozumel it was more than the water temperature. Corals can withstand prolonged temperaturs of 86 without a concern, and 87 starts them showing signs of unhappiness, and then 88 is a full on stress. This is under ideal conditions.

Cozumel reefs are no longer under "ideal conditions". The amount of nuisance algae and cyanobacteria growing on the seabed is a clear indication that water quality is suffering. Clearly Cozumel waters are higher in dissolved organic compounds (aka wastewater runoff) than we (or rather, the corals) want.

When you start adding other stressors to the mix, such as higher than normal DOC, suddenly water temperature and the dissolved oxygen levels start having a bigger impact.

Cozumel never got below 80 degrees this winter. Traditionally we would drop to 78 mid-winter before starting the summer climb. I didnt see us get below 81 for the winter, so it's fair to say we are starting the climb at 3 degrees higher than normal. This has me very concerned. Does last year's 88 become this year's 91? That would be disasterous. I am hopeful ocean currents can churn up the deep and send up regular cold water upwellings. At this point it might be our only hope.

 

[DeltaWardog]

The chickens are coming home to roost.

If you care about this stuff, vote appropriately. It's probably too late, but some mitigation might be possible. If we continue down the path we're on, the last generation of reef divers has already been born.

 

[ggunn]

The chickens are coming home to roost.

If you care about this stuff, vote appropriately. It's probably too late, but some mitigation might be possible. If we continue down the path we're on, the last generation of reef divers has already been born.

Last summer was horrendously hot here in Austin and we are bracing for what is being widely forecast as what will be an even hotter summer this year. Most of last summer it was just too hot to do anything outside during the day, and at night it wasn't all that much better.

 

[WillieJustice]

Last summer was horrendously hot here in Austin and we are bracing for what is being widely forecast as what will be an even hotter summer this year. Most of last summer it was just too hot to do anything outside during the day, and at night it wasn't all that much better.

I had an old Chevy van I used for work and pretty much everything else. My grim joke was that I was making Seattle into the tropical paradise we all thought it should be. It's not nearly as funny any more. We may have wildfires on the west side of the Cascade Mountains. It's not just reefs that are being destroyed. It is everything.