More Bad News for Caribbean Coral Reefs

[bobconnie]

Darn and I thought all us cruisers caused the death of the coral heads, by anchoring improperly in coral !! It seems like just a short time ago when the Govs said it was us doing the damage by anchoring !! Things sure change fast !! Mostly from what Ive seen with my own eyes, cemicals are the biggest killer of coral, and sewage run off is right up there with it !! Just my 2 cents

[rubyjean]

If.....We could all live to be a thousand years old, we could see for ourselves what's happening. I just don't belive that Al Gore has a clue. By the way, he didn't invent the internet....That's my story and I'm sticking to it...Michael..

[conachair]

Over 30 posts without getting shut down, well done everyone

So since the suns solar output has been declining for the past 3 decades, just where is all that energy coming from to heat the planet then?

[conachair]

Originally Posted by avb3

That's because no one has really needed to be shown this yet.

Linky no work And I really want to see it now that I can't

Another one from further north.

Arctic Sea Ice News and Analysis | Sea ice data updated daily with one-day lag

These things always seem to get completely polarized, it's either this or that. Fertilizer runoff and over fishing more than likely do play a part, but no matter what digging up 1,324,512,000,000 barrels of oil every year and setting fire to it cannot be a very good idea for long term survival. No that much will change until something forces it. Humans aren't great guiding their path as a species. Any more than a plague of locusts. But that's not really anyone's fault so don't let it spoil your day

[Andrew Troup]

Originally Posted by conachair

....
So since the suns solar output has been declining for the past 3 decades, just where is all that energy coming from to heat the planet then?

Umm ...... the sun? (other potential sources are absolutely tiny by comparison)

Firstly, 'declining' is a big word. The solar energy input varies cyclically, but the variation is small fractions of one percent.

Perhaps I don't understand the question.

The greenhouse effect hypothesises that the proportion of solar energy retained in the atmosphere is increased as the concentration of certain gases rises. This effect is still only a fraction of one percent, but a LARGE fraction. Hence it would swamp cyclical variations of the sun's output.

IF solar forcing is decreasing and yet the planet continues warming, (in the absence of large-scale, ongoing nuclear destruction of mass) surely such a divergence would appear to support the hypothesis.

It would also ring further alarm bells: if we were seeing this much warming even under a declining input of solar energy, how much worse would it get when the solar cycle reverses?

[jrod321]

I think fisherman bleaching the reefs is to blame, not warming of the waters. While the practice is illegal, it still happens often.

For those who don't know what I'm talking about, one way of destructive fishing involves dumping bleach, or some other killer compound directly on the reef, when this happens all the fish on the reef come out of hiding(sometimes stunned) to seek clean water. This makes for easy prey to the fisherman, the rest is left for dead including the reef.

[Blue Stocking]

The term "coral bleaching" with which I am familiar, does not refer to pouring bleach on a reef. It is a term used by the scientists to describe the cyclical dying off of certain types of coral, which historically regenerate in a few years.
The living organisms die, and leave behind the Calcium shell, which is pale yellow.
Our reefs, (Bermuda), which, because of the Gulf Stream, are the Northern most coral reefs in the world, went thru this cycle about 10 years back. They have now recovered.
I have 300 ft of waterfront, of which a large portion is considered "nursery habitat".
I also live 1000ft feet up the shore from the Bermuda Institute of Ocean Science (BIOS) which I support, and whose work I follow closely.
Sea Urchins, Cucumbers, Turtle Grass, Spanish Scallops, Seahorses, and others, have come and gone in about 5 year cycles that I have observed from my dock, over the past 27 years .
No doubt polution can kill off species, but nature is also a great regulator.
I have no professional qualification in this field, but have been diving our reefs my whole life.

[jrod321]

Dumping chemicals on the reef to cause all the fish to come out really does happen, and my understanding is bleach really is used. It kills everything and is worse than dynamite fishing for the eco-system. It still happens and I'd be willing to bet that bleached reefs in the Caribbean that have been blamed on global warming were in fact caused by this method of fishing.

[Blue Stocking]

You are probably right. My first paragraph could have been less adamant. No offense meant.
Our experience with this, some years ago, were random spots, and IIRC, one particular type of coral.

[Therapy]

Originally Posted by jrod321

Dumping chemicals on the reef to cause all the fish to come out really does happen, and my understanding is bleach really is used. It kills everything and is worse than dynamite fishing for the eco-system. It still happens and I'd be willing to bet that bleached reefs in the Caribbean that have been blamed on global warming were in fact caused by this method of fishing.

When discussing this, all need to remember there are two distinct and different definitions of "bleaching" here. Neither one has to do with the other.

I am sure that for some it does not matter as it all has to do wih MMGW.

[jrod321]

Not offended but I do feel more of us need to be aware of whats happening with our reefs. I am only 29 but I have seen too much of our planet destroyed on land and in the water.

[Therapy]

Originally Posted by jrod321

Not offended but I do feel more of us need to be aware of whats happening with our reefs. I am only 29 but I have seen too much of our planet destroyed on land and in the water.

I have sons 23 and 25 and I feel sorry for all three of you.

[Andrew Troup]

Originally Posted by jrod321

Dumping chemicals on the reef to cause all the fish to come out really does happen, and my understanding is bleach really is used..... I'd be willing to bet that bleached reefs in the Caribbean that have been blamed on global warming were in fact caused by this method of fishing.

I guess your money is safe, because your understanding appears to be based on belief.

In case you are interested in evidence, it might interest you to reflect on wider cases than just the Carribean:

"The 1998 bleaching event saw catastrophic bleaching with massive mortality occurring on reefs in Bahrain, Maldives, Sri Lanka, Singapore, and parts of Tanzania."
This coincided with the highest sea water temperatures ever recorded at that time.

The 1998 and 2002 years also saw sea water temperatures several degrees above normal on the Great Barrier Reef in Australia, both of which coincided with major bleaching (although not as catastrophic as the worst cases found elsewhere). You may not be aware that the use of chemicals for fishing is not widespread in places like Australia and Singapore, if indeed it happens at all.

However, just because high temperatures coincide with mass bleaching, doesn't establish beyond scientific doubt that they cause bleaching.

In Australia, they were sufficiently concerned about linking the supposed cause to the observed effect to set up programs like this:

"Here we discuss the development and testing of ReefTemp, a new operational remote sensing application for the Great Barrier Reef that assesses bleaching risk daily using: high-resolution (2 km) Sea Surface Temperature, regionally validated thermal stress indices, and color-graded legends directly related to past observations of bleaching severity."

Bleaching has also been observed to be correlated with temperature at coral atolls which are uninhabited and beyond the reach of fishing activities.

This is how science (when applied properly) verifies a theory (such as your theory that bleaching results from the use of bleach): it looks for situations which would DISPROVE the theory, such as reefs subject to thermal stress but NOT chemical stress, to see if the same damage is observed.

As a result of hundreds of independent studies, looking for other possible explanations and failing to find them, it can be asserted with some confidence that

"Anomalously high sea surface temperatures (SST) have led to repeated mass coral bleaching events on a global scale."

[cfarrar]

My layman's understanding about coral and climate change is that it's not the warmer temperatures that kill the coral. It's the rise in atmospheric CO2, which is stored in the oceans via the carbon cycle, lowering the pH. Coral are sensitive to pH. At least that's one of the hypotheses. And yes, sewage, fertilizers, and other pollution don't help, but the bleaching phenomenon is a global one, affecting remote areas as well as reefs closer to human settlements.

I wish I could see the reefs as they were when I began diving 35 years ago. Sadly, every reef I've seen in the last 15 years is a pale shadow of its former glory. Every time I'm told by someone that a particular spot is "still beautiful," or "coming back," I get my hopes up, but I'm always disappointed. Those of you who dived a few decades ago know what I'm talking about.

[cfarrar]

Just to be clear, I'm not saying that sea temperature doesn't correlate with coral bleaching. In fact, higher sea temperatures probably allow for higher CO2 levels. Maybe someone with more knowledge or a well-written study can clarify this.

Colin