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Corals bleached in 1862 by all the cars and coal plants that didn’t exist

Peter Ridd writes that a new paper uncovers rare lithographs of corals underwater in 1862.

One hundred and fifty year old pictures of corals are rare enough, but these ones had the unmistakable pure white cauliflower look that marks them as totally bleached. But in 1862 the first coal fired power plant was still twenty years away from starting work as a coral destroyer, and carbon dioxide levels were a perfect 286ppm.

This is the spot (below) in the Northern Red Sea just at the end of “The Little Ice Age”. Perhaps the seas were too alkaline then, and were yet to reach the perfect pH nirvana they must have struck the year before humans started scuba diving en masse.

Coral bleaching, lithograph, 1862.

Bleaching in 1862, twenty years before the worlds first coal fired power plant was built. Ransonnet 1862  |  Tomas Cedhagen 2021

We can see why scuba diving was not popular in 1862.

Figure 1. Diving bell constructed by Eugen von Ransonnet and used in the Red Sea and tropical Asia. Left: Sketch from Ransonnet (1867) showing the diving bell. The diver could move forward in any direction by simply raising the weights BB (textile bags with cannon balls), while the boat with the air-pump followed in his wake

The first underwater camera had a little man inside?

 

Somehow the great marine-psychics of the world know that corals didn’t bleach in the early 1960’s even though, or perhaps “because”, there was almost no one down there to see it.

From Peter Ridd:

Reef-scientists often claim that coral bleaching is a new phenomenon that only started in the 1970’s due to climate change. But a remarkable new paper published by Tomas Cedhagen, of Aarhus University in Denmark has uncovered a very early lithograph showing bleaching in 1862.

There are actually many other early observations of bleaching, including by Sir Maurice Yonge in the first major science expedition to the Great Barrier Reef in 1929 (if you don’t count Captain James Cook’s scientific exploration of the reef in 1770). But Eugen von Ransonnet’s remarkable lithograph, taken from an incredibly crude diving bell, seems to be the earliest picture.

People arguing that bleaching is new might argue that the important point is that there was no MASS coral bleaching before the 1970/80’s. Von Ransonnet’s lithograph is evidence only of bleaching on a small scale.

This argument is incredibly weak for the following reasons.

(a) In order to observe mass coral bleaching, it requires a major monitoring effort designed to measure such a large-scale event. Before about 1970, there were very few marine biologists and no major institutions capable of doing such monitoring. Von Ransonnet, in his diving bell was certainly not in that position. Marine science is a very new discipline, so it is not surprising that the mass coral death events, and the huge coral spawning events were unknown to science until a few decades ago. The first proper aerial surveys were not carried out until 1998. And would anybody argue that mass coral spawning, that was only discovered in the early 80’s, never happened before that date.

(b) If a few corals bleached in 1862, or 1929 (Yonge), due to hot or cold water, why would we suppose that the same hot/cold event did not bleach corals elsewhere in the same region?

(c) On purely statistical grounds, large scale very hot events must have occurred before 1970. Perhaps not as frequently as today due to the warming climate, but they must have occurred. And its not as though the climate has got very much warmer in the last 100 years (from whatever cause). The reef water is at most just 1oC hotter. Major bleaching events must have occurred in the past unless you believe that all the corals on earth were precariously close to their upper thermal limit.

But despite this, Prof Hughes of JCU stated on ABC radio.

…a critical issue here is that these bleaching events are novel. When I was a PhD student 30 years ago regional scale bleaching events were completely unheard of. They are a human invention due to global warming.

This seems highly improbable.

References

Cedhagen, Thomas (2021) Coral bleaching recorded during the little ice age. Phuket mar. biol. Cent. Res. Bull.78: 21–28 (2021) DOI: 10.14456/pmbcrb.2021.1

 

9.7 out of 10 based on 118 ratings

145 comments to Corals bleached in 1862 by all the cars and coal plants that didn’t exist

  • #
    Kalm Keith

    That’s a fascinating “lithograph”, which brings up the question of how it was made.

    The sketch of the diving bell seems to indicate that the picture was hand drawn first.

    On surfacing, the artist would perhaps have finished off the drawing and then coloured it in by hand, the colours being done from memory.

    Then it would have been off to the lithographic process which enabled multiple copies to be pressed.

    Certainly nothing like modern colour photography.

    Still, a valid piece of scientific observation from 158 years ago.

    Loved the shark in the background.

    240

  • #

    I like scientific art.

    The Red Sea, for coral, has the benefit of being really deep. While the coral grows close to the surface on walls and small reefs, you still have less temperature fluctuations than shallower seas. It also benefits from being surrounded by land that is desert, so less run off (although in the winter there are flash floods). And very low population densities (at least until recently).

    Coral bleaching can be triggered by temperature. It can also be triggered by other factors too. Still an interesting thing to see bleaching in 1862.

    30

  • #
    Graham Richards

    I suppose we can assume the bleaching was caused by acidity caused by hundreds of thousands of Arabs taking a leak while swimming in the sea. The “warmists” will find someway of blaming humans for this event, so I thought I’d give them a hand!

    330

  • #
    Simon

    Nobody is suggesting that coral bleaching did not happen in the past. It is a defense mechanism that has evolved over millions of years. The question is one of scale and duration. It’s a last ditch defense, corals can recover but only if the water temperature returns to an habitable level before the coral dies.

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    • #
      Raven

      Nobody is suggesting that coral bleaching did not happen in the past.

      Well, Simon, that’s precisely what Prof Hughes is implying.

      780

    • #
      Peter Fitzroy

      It is the frequency not the occurrence of bleaching which is the problem, and Peter Ridd et al should know that.

      Terms like niche specialisation, speciation and evolution are beyond what most people on this blog understand. Still when ignorance got you this far, why do research

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      • #
        Harves

        Lol. Fitzroy implying that he knows more about coral bleaching than Peter Ridd. You just cannot make up such arrogance.

        900

        • #
          Graham Richards

          Have you noticed that when “ warmists” & their ilk have facts thrown at them They revert to nit picking and use semantics to try & divert attention!
          “Terms like niche specialisation, speciation & evolution “ are beyond the comprehension of us peasants?? I suppose we have trouble with big words like “ marmalade “ as well.
          What an arrogant dick head!

          700

          • #
            David Maddison

            Graham, they either do as you said or just simply alter or delete the facts.

            390

          • #
            Hasbeen

            October 1972, I had spent 4 months cruising the reef between MacKay & Townsville. On a passage from the Whitsundays to Middle Percy Island I encountered huge patches of a horrible brown sludge floating on the water. Nasty stuff, stained the topsides brown if not cleaned off in minutes.

            At Middle Percy I ran into John, the reef fisherman, come in from the Swains to fill his water tanks. These blokes spend more than half their lives on a boat out the reef. They stay fishing, until their freezer is full. That will take weeks, may be a month, then a few days off in Mackay for John, before back to the reef. He had been doing this for aver 20 years then, starting as a deck hand at 14.

            When I complained about this brown sludge I’d encountered he explained the coral spawning phenomena. He’d been experiencing it for 20 years & understood just what happened.

            This was over 10 years before our esteemed coral scientists first discovered it. Perhaps one of them had talked to the true reef experts, the fishermen who live out there.

            It is not surprising the fishermen know more than these scientists, after all they spend a life time out at the reef, not just a few weeks a year at Lizard at Heron island research stations.

            I had met John a few months earlier, “out the Swains”. It was pretty rare for an amateur yachtie to venture out there in the 70s, & he took me under his wing, teaching me as much as I could absorb at the time.

            Years later I had some dealings with the Marine Park Authority & AIMS, when running one of Australia’s biggest marine tourist operations based in the Whitsundays, & I know who I would ask if I needed information on the reef.

            330

            • #
              Kalm Keith

              Hasbeen, in a real world, people like John would be more deserving/eligible of a PhD than 97% of recent recipients.

              230

          • #
            Tel

            And constant attention shifting … it’s THIS thing that really matters … wait, it’s these OTHER things that we should look at now. No I didn’t say anything like THAT … look over THERE!

            40

        • #
          Melissa

          Oh Harves, Peter is only expressing the view of climate scientists, which Ridd has yet to refute factually.
          The arrogance of the cherry picker

          013

          • #
            clarence.t

            You are so right.

            Peter Fitzroy does show all the arrogance of a cherry picker.

            But what other occupation is he fit for !

            And one does not have to refute obvious frąȗd and scientific misconduct (at JCU)

            All they have to do it bring it to the light of day.

            Well done Peter Ridd.

            50

        • #
          Peter Fitzroy

          On coral bleaching yes, I know more than the attention seeker Ridd. And in General I know way more than you.

          057

          • #
            clarence.t

            BS.. You pretend to yourself that your know more.

            But invariably get proven wrong.

            You are in fact, a negative when it comes to actual knowledge.

            400

          • #
            Kalm Keith

            Mr. Fitzroy.

            As you have requested below, I would like to apologise and have prepared a fairly lengthy document on 50 sheets of A4 paper.

            It’s rolled up ready for delivery.

            Could you please indicate where you want it delivered?

            Yours in heavy anticipation,

            KK

            90

          • #
            GD

            On coral bleaching yes, I know more than the attention seeker Ridd

            Peter Fitzroy, how many times have you dived the Reef?

            I did many times in the 70s, both snorkeling and scuba-diving. It was a magnificent experience. Our diving club was based at the Tobruk Baths on the Strand in Townsville. Older members of the club organised regular trips to the reef. Usually, we’d hitch a ride with a local fishing charter. This involved boarding an old stinky fossil fuel charter boat at 5am at the Flinders Street dock.

            The fishermen went out regardless of the weather, so I got to experience the roughest weather of the reef and the best weather.

            On other occasions, I’d score a luxury trip to the reef on a local doctor’s yacht. Thankfully, the doctor only went out in fine weather and embarked at a sensible hour.

            Peter Ridd, on the other hand, has dived the reef for decades.

            Peter Fitzroy, how many times have you dived the Reef?

            60

      • #
        clarence.t

        You have absolutely zero evidence of increased frequency of bleaching.

        Anyway, the recent bleachings, now recovering beautifully, were due to low water levels due to the large El Nino, nothing to do with CO2 or “climate change or acid water.

        Basically everything is beyond your understanding, Peter.. so why persist in proving it.

        Your ignorance is making you a laughing stock… Never any research or science from you.

        600

        • #
          Melissa

          Have you bothered to look at the CSIRO site lazy boy?.

          18

          • #
            clarence.t

            Lol.. CSIRO are deep into AGW activism. Why would anyone trust them on anything ?

            Yes the reef is recovering..

            Yes, the El Nino caused a low sea level event which exposed the coral to more solar energy than usual

            Sorry you don’t seem to understand that.

            60

          • #
            clarence.t

            Do you have knowledge of the frequency of bleaching events around the 1880-1910 period.. hottest period in Australia’s history?

            Do you think the reef didn’t bleach at any time over the last 10,000 years of the Holocene, most of which has been warmer than current temperatures?

            You have nothing !

            50

        • #
          Peter Fitzroy

          Occurring at an average rate of once every 25–30 years in the 1980s, mass bleaching now returns about every six years and is expected to further accelerate…. Severe bleaching is now occurring more quickly than reefs can recover, with severe downstream consequences to ecosystems and people.
          https://www.climate.gov

          Apologies will be accepted now

          147

          • #
            clarence.t

            Yawn,

            You have no idea what so ever what the bleaching was like around the 1900’s temperature peak in Australia.

            You have no idea whatsoever what any bleaching was like during most of the last 10,000 years of the Holocene.

            \Let’s just face it.. You have no idea whatsoever.

            Reef is recovering beautifully from the strong El Nino low sea level event a few years ago.

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          • #
            clarence.t

            And the far-left activist “climate.gov” , seriously ????

            Who listen to the 110% activist, minus 10% scientist Terry Hughes?

            210

          • #
            clarence.t

            “with severe downstream consequences to ecosystems and people”

            What a load of mindless activist garbage.

            Reef is recovering very well from the 2015 El Nino low-water outflow event…..

            Hard coral back up above 1990 levels except in cyclone (weather) affected areas.

            https://i2.wp.com/wattsupwiththat.com/wp-content/uploads/2021/06/image-85.png

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          • #
            clarence.t

            “average rate of once every 25–30 years in the 1980s”

            I bet you don’t even realise how dumb that statement is. !

            240

            • #
              Richard Jenkins

              Clarence
              Get Peter’s counters, 1980 +25 = 1982
              1982 + 30 = 1985
              1985 + 27 = 1987
              1987 + 28 = 1989
              See that’s an average of 25-30 years in a decade!
              They checked the whole reef using submarine drones and GPS even before they were invented.

              110

            • #
              Melissa

              Clarence, once you calm down, can you show why every reputable scientific body on the planet is wrong and you’re right ?.

              02

              • #
                clarence.t

                Studies of the GBR only go back to the 1970s

                That is a totally insignificant time span

                Do you deny that Australia was warmer in the late 1800s,

                Do you deny that for most of the last 10,000 years the planet has been significantly warmer than now.

                And yes, science does show significant GBR bleaching frequency in the 1860s and even back to the 1700’s

                Because that is what all “the science” tells us.

                Or were you unaware (ie ignorant) of those facts?

                If so, you should do some research and become less unaware.

                30

              • #
                clarence.t

                Valerie Taylor swam and filmed on the GBR for many years

                She noted strong bleaching in 1965, recovered by 1970

                Try not to remain unaware. !

                ———–

                Also, Ocean temperatures have been much warmer in the not too distant past

                https://i.postimg.cc/y6PJqFff/OHC-in-perspective-2.jpg

                Do you really think bleaching has never happened before ?

                10

              • #
                Brian

                Pe3rhaps Melissa, its because they quickly came to understand upon which side their bread was buttered? Certainly true of the Institute for which I worked

                20

          • #
            Deano

            Yes – I checked out what http://www.climate.gov says about the reef and I notice they quote studies from James Cook Uni. I find it hard to trust claims coming from a source that sack staff members who behave like scientists – reporting the truth no matter what current fashionable thinking demands.

            90

          • #
            el gordo

            ‘ … mass bleaching now returns about every six years and is expected to further accelerate …’

            That is simply not true, over the next decade El Nino won’t be active, so the reefs within the western Pacific coral triangle will return to pristine beauty.

            Looking further afield, the Red Sea region is about to enter a cooling phase for a few decades, when a negative Atlantic Multidecadal Oscillation cools the surface of the Red Sea.

            The bleaching in that region around 1862 was because of this oscillation, a drop of only one degree in a heat tolerant reef will produce massive bleaching.

            00

          • #
      • #
        Kalm Keith

        “Terms like niche specialisation, speciation and evolution are beyond what most people on this blog understand.”

        Koalas are a good example of niche habitat. The only problem is that they get habituated to it and can’t function elsewhere.

        230

        • #
          Graham Richards

          KK, please explain the meaning of “ habituated”! I’m one of the uneducated masses that won’t believe the global warming class! Can’t believe the arrogance of of this fraud.
          Here I was thinking that the biggest fraud on the planet was POTUS,

          140

          • #
            Kalm Keith

            🙂
            I just took habituation to be the same as the term “niche specialisation” but less pretentious.

            It was 97% sar chasm so don’t take it too seriously.

            70

      • #
        R.B.

        If you were really any better than us, Peter, why not correct Simon?

        When depletion was not extreme, recovering corals generally contained the same types of zooxanthellae as they did prior to treatment. After severe depletion, however, recovering corals were always repopulated by zooxanthellae atypical for their habitat (and in some cases atypical for the coral species). These unusual zooxanthellar associations were often (but not always) established in experimentally bleached tissues even when adjacent tissues were untreated

        With slow warming, you get will migration of zooxanthellae that prefers warmer water repopulating bleached coral before it starves. The extreme warming are events that have always happened and global warming can not explain them, but might be a degree warmer than when the above photo was taken. Cyclones will not be more likely. Sun damage will be less likely, so survival until being repopulate more likely.

        The assertion that warmer waters will stop depopulation is just ignorance of science – not “listening to the science”.

        170

      • #
        David Maddison

        Peter, the Left have always claimed coral bleaching was a new and unprecedented phenomenon. They have never claimed that bleaching events were simply more common now.

        Now faced with facts, you change the narrative

        That is, until Leftists can have this “inconvenient fact” altered or erased.

        240

        • #
          David Maddison

          Peter, I used to think you were a bit of a troll, now I am further disturbed that you might actually truly believe your own nonsense.

          250

      • #
        Bob Fernley-Jones

        Funny how Hughes’ first aerial survey that described a mass bleaching event was in 1998 during what was the second defined “Super El Nino”. There was no aerial survey in the first such event in 1982/3, although widespread local bleaching was reported. The reportedly biggest event in 2016 coincided with the third defined “Super El Nino” and, there is much evidence that the event in 2017 was a result of c/o disruption to ocean circulations, notably the East Australian Current out of the Equatorial.

        These events are “poorly understood” (unpredictable) and have not been shown to be connected to global warming.

        As for the Hughes and media scare of April 2020:

        Great Barrier Reef found to be coral bleached from north to south for first time

        Funny how it all then went quiet and the GBRMPA’s Reef Health report found it was nothing to get excited about. Check September 2020, the most relevant chapter.

        Coral bleaching and disease:
        Our Eye on the Reef network reported isolated instances of low severity coral bleaching and damage in all management areas. Isolated instances of low severity coral disease were reported from all areas, except the Far Northern management area.

        As for Fitztroy’s assertions on frequency, compare this (for instance) from an authoritative source:

        Large-scale coral bleaching was recorded as early as 1931, but severe bleaching on a regional or global scale was not documented until 1983. We use records from a global database of bleaching records to show that severe bleaching events occurred at a global level on four recent occasions and demonstrate that these events occurred in close temporal proximity to a strong negative deviation in the Southern Oscillation Index. While there was no clear increase in the frequency or intensity of major global bleaching events, the number of bleaching records clearly increased during the past three decades. However, increased vigilance and reporting of mild bleaching by an ever-increasing number of researchers and conservation-minded divers has confounded efforts to definitively separate changes in bleaching frequency from changes in reporting.

        80

        • #
          Richard Owen No.3

          Careful Bob:

          Peter has an M.S.C. from James Cook University.

          That isn’t a Science degree, Peter has never mastered science.
          Rather it stands for Makes Silly Comments.

          90

          • #
            Bob Fernley-Jones

            Richard Owen No.3

            If ex Professor Ridd, the former Head of Physics at JCU, only gained a masters degree at that university as you say, then he has done rather well don’t you think?

            Re https://www.jcu.edu.au/news/releases/2013/october/time-to-act-on-maths-science-in-schools in 2015

            00

            • #
              Richard Owen No.3

              Bob:

              I went to Adelaide University which had a somewhat inflated sense of its own importance in that it only recognised degrees from other Australian universities (a limited no. in those days), Oxford & Cambridge, Edinburgh, and Trinity College, Dublin (and London School of Economics in that discipline only). The renowned Professor of Geology only figured in official literature as BSc. That he had a DSc from the Colorada School of Geology (then, and for long after, the top Geological Instiution in the World) wasn’t considered worthy of notice.

              Earlier they had someone from Europe with a Medical Degree from Groningen University (the top European), who was told to start studying in fourth year towards an Australian qualification so he could practice. This he did diligently, always in the front row of the lecture hall making notes, until the last week of lectures when the lecturer made some remark with which he disagreed and and stood up and said “dast ist not so”. The lecturer over-ruled him saying “look in the course text book”. The rejoinder was “I wrote the text book”.
              He sat for his exams and was called up to an interview with the Professor of Medicine (and 2 others), and The professor formally shook his hand and said “Congratulations, you have passed your fourth year examinations. Now this is my colleague Dr. X who has a question for you”. Dr. X asked his question which was discussed between them for some minutes the the Professor of Medicine shook his hand again and said “Congratulations, you have passed your fifth year examinations. Now this is my colleague Mr. Y who has a question for you” After about 10 minutes of discussion The professor formally shook his hand and said “Congratulations Doctor, you have passed your final examinations for your degree. Perhaps you would like to join us at lunch because Dr. X has a position that he wants filled”

              The bureaucrats were incensed about this shortcut (regardless of his merit) but the Professor of Medicine pointed out that the University foundation Charter specified that the (5 foundation) professors could set what examinations they deemed appropriate. All they could do was amend the Charter so someone, however qualified, had to follow their rules.

              90

            • #
              clarence.t

              Peter Ridd received a Bachelor of Science degree in Physics from James Cook University in 1978, and later a PhD in Physics from that same institution in 1980.

              At this time, he also joined the Australian Institute of Marine Science. He started studying the Great Barrier Reef in 1984, mainly focusing on ocean currents and the movement of sediment.

              While teaching at James Cook University, Ridd was the head of the Physics department from 2009 to 2016, and head of the Marine Geophysical Laboratory at that institution for 15 years.

              40

          • #
            Sceptical Sam

            Peter has an M.S.C. from James Cook University.

            Nonsense.

            If you knew anything, you should know that there’s no such thing as an M.S.C. in any Australian university. JCU included.

            Here’s the list of Institutions and Qualifications from Australian universities:

            https://qual.app.uq.edu.au/qualifications/

            Find M.S.C. for us.

            20

          • #
            clarence.t

            I thought Peter F had a M.BS !

            10

      • #
        Sceptical Sam

        It is the frequency not the occurrence of bleaching which is the problem

        The more you look, the more you find, Peter.

        How many millions of dollars were provided by the Australian taxpayer for the study of coral reefs in the 1950s?

        The numbers of eyes now looking has grown faster than a greeny’s fear at a cigar club meeting.

        70

      • #
        TedM

        Please give us the documented bleaching frequency pre 1900 Peter.

        10

      • #
        Ronin

        Oh look, our two resident Marine Biologists, Simon and Fitzy, how lucky are we to have them.

        60

        • #
          el gordo

          Simon is good value, I have learnt something useful, but Mr Fitzroy is out of his depth when it comes to marine science.

          20

      • #
        Bob Fernley-Jones

        Fitzroy,
        Another example of the commonality of coral bleaching and your unfounded claims of increased frequency is demonstrated at this website:

        Dr Alison Jones is a research scientist focusing on coral reefs in the Keppel Islands of the Great Barrier Reef.

        She reports with [4 references]:

        Mass bleaching was recorded in the Keppels in 1998 [62], 2002 [63] and 2006 [64] and 2020 with minor bleaching in between.
        There are also unofficial reports by local fishermen of bleaching in 1983 and 1987 [65].
        There is no evidence to suggest that there has been an increase in the frequency of bleaching events.

        Note that 1983 pops up again.

        50

      • #
        tom0mason

        Evidence from Bikini Island corals where they were subjected to some human caused bleaching when the H-Bomb was tested there. Yet despite all the alarm about global warming wiping out corals, Bikini Islands soon recovered and are now thriving.
        If these very robust creatures can survive that, then I am sure the minuscule amount of warming envisage by global warming advocates will have no appreciable effect on them in the long term. Sure there numbers and types will vary (as they do naturally) but they are very, very likely to be OK as they are very robust creatures.
        Atmospheric CO2 does not control the planets temperature, and a warmer planet better sustains life.

        10

    • #
      Travis T. Jones

      Perfessor Terry Hughes –

      Terry Hughes: “I showed the results of aerial surveys of #bleaching on the #GreatBarrierReef to my students, And then we wept.”

      https://twitter.com/ProfTerryHughes/status/722512223067721728

      The first bleaching on the #GreatBarrierReef was in 1998. There is no “cycle”

      https://twitter.com/ProfTerryHughes/status/722653679841624064

      Oh dear.

      Can the good perfessor do research?

      Bleaching has been observed on the Great Barrier Reef since 1982,
      http://www.bom.gov.au/oceanography/oceantemp/GBR_Coral.shtml

      370

      • #
        Travis T. Jones

        Terry Hughes, Distinguished Professor (in scaremongering), James Cook University: We just spent two weeks surveying the Great Barrier Reef. What we saw was an utter tragedy

        “The first recorded mass bleaching event along Great Barrier Reef occurred in 1998, then the hottest year on record.”

        https://theconversation.com/we-just-spent-two-weeks-surveying-the-great-barrier-reef-what-we-saw-was-an-utter-tragedy-135197

        100

      • #
        sophocles

        that climate change is killing polar bears

        so we have to ban polar bears and climates?

        40

      • #
        Just Thinkin'

        The people of North Queensland knew all about “coral bleaching.”

        They used to gather the dead coral and use it with cement for
        concreting.

        Then it was “discovered” by the scientists.

        Game over.

        I think it was about the same time “scientists” found out
        about coral spawning. I could be wrong about that last bit.

        00

      • #
        Hasbeen

        You can not tell the colour or health of coral from an aircraft. I tried it from a Air Whitsunday Lake Buccaneer sea plane in 1985. With calm water all you see is a mirror reflection of the sky, & with choppy water you get too much light scatter to get much idea.

        Even landing & looking from the drifting aircraft was useless. You need your head under water with goggles to see anything much.

        Yes you can tell where the coral is & isn’t, & can get some idea of how deep it is, but if you could see the coral that simply, people would never have invented glass bottom boats.

        I was looking for a spot for an installation for tourist trips. It took 4 days for 2 of us in the water, swimming & drifting with the current to properly survey a 1.5 mile ribbon of reef to find the best coral for viewing.

        Flying over the reef is pointless as you learn nothing.

        60

    • #

      Coral bleaching is associated to climate change as the association that climate change is killing polar bears.

      250

    • #
      GlenM

      You guys have got to stop listening to the ABC and like. Obvious to others here that your dissonance has got the better of you.

      100

    • #
      el gordo

      ‘… but only if the water temperature returns to an habitable level before the coral dies.’

      As Clarence mentioned, bleaching in the coral triangle has nothing to do with water temperature. Sea level fall over a few days, caused by a strong El Nino, sees the polyps clear out. They hate being exposed.

      140

      • #
        Simon

        El Niño reduces the sea level only by a couple of cm off the Australian coast. Recent unprecedented mass bleaching events are due to localised warming of sea temperatures.
        E.g. https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2017GL074877 makes no mention of sea level reduction.

        010

        • #
          el gordo

          ‘ … we concluded that local meteorology has been the primary cause of coral bleaching on the GBR during El Niño events over at least the past 34 years.’

          That is a novel approach, worth closer examination, and its gratifying to know that AGW its not responsible.

          30

        • #
          el gordo

          Here is an example of bleaching and El Nino was absent, so we might be onto something beyond our mutual understanding.

          https://www.abc.net.au/news/science/2019-05-21/coral-bleaching-french-polynesia/11129634

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            Peter C

            Maybe it has nothing to do with warm water.

            Quote:

            “We have seen bleaching all the way down to 100 metres. But it’s worst on the shallow, sheltered reefs.”

            Coral bleaching occurs when high water temperatures cause the coral to expel its symbiotic algae, revealing the white skeleton beneath.

            They repeat the manta that high water temperatures are to blame, but it lacks credibility.

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              Tel

              Coral grows in a wide variety of water temperatures, but on the whole tends to prefer warm water. The GBR spans about 14° of latitude meaning that the temperature at one end is nowhere near the temperature at the other end.

              It’s been there for millions of years, and has survived far greater climate shifts (both warmer and cooler than today) than human civilization has seen. The GBR survived the Younger Dryas period which was the most rapid sudden warming event in recent geological history (approx 12000 years age).

              … but it lacks credibility …

              It doesn’t even pass a quick back of the envelope check.

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            clarence.t

            el-g, read the section titled “Multiple causes of bleaching

            at this link https://judithcurry.com/2016/05/24/coral-bleaching-debate/

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          beowulf

          You’re out by a factor of 10 Simon — 200mm drop in 2016 for instance.

          https://wattsupwiththat.com/2017/10/02/great-barrier-reef-2016-coral-cover-loss-and-local-sea-level-fall/
          See:
          Figure 9. Coral cover loss and local sea surface height. Note that the areas with most severe coral cover loss in 2016 experienced a sharp (~0.2 m) drop in sea surface height from 2014-2016.

          Source: Great Barrier Reef Marine Park Authority 2017, Final report: 2016 coral bleaching event on the Great Barrier Reef, GBRMPA, Townsville. Sea Level Research Group
          University of Colorado.

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            el gordo

            The 2015-16 El Nino was strong and coincidentally a marine heatwave sprang up in the Tasman Sea (lasting 251 days) and Sydney’s coral bleached.

            Was it a fall in sea level or warmer water doing the damage?

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              clarence.t

              1. Exposure of coral due to low sea levels

              2. Low sea levels allow warming of the surface by solar energy (pools are much warmer than ocean water and have less dissolved oxygen.)

              3. The flow of warmer is away from the reef, so not bringing in the normal flow of micro-creatures and nutrients for food.

              None of this is to do with CO2 forced “climate change”

              And no, its not “damage”, its the critters that inhabit the coral going for a holiday.

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                el gordo

                Good argument and I accept that bleaching is a natural function and the word ‘damage’ is inappropriate.

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          Just Thinkin'

          Simon,

          and I suppose the age of the coral would have nothing
          to do with it?

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      R.B.

      People first noticed coral bleaching events in the 1980s.

      National Geographics
      Its a well entrenched part of the propaganda.

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        Richard Owen No.3

        R.B.

        B.S. I was told about it in 1961 on a school trip there. It wasn’t called bleching then, just “goes white, and comes back in a couple of years”.

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        Ronin

        I got a National Geographic out of my local library last year, I could not believe how leftard it has become.

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    David Maddison

    Let’s hope the original of that lithograph is not “disappeared” or altered, as is the practice of the Left when confronted with information they disagree with like historic temperature records.

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    a happy little debunker

    30 years ago regional scale bleaching events were completely unheard of. They are a human invention due to global warming

    During the last Ice Age vast areas of the GBR were completely uncovered and exposed to direct sunlight – a mass ‘bleaching’ event of epic and prolonged proportion – with an absolute absence of global warming…

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    Travis T. Jones

    Now that lithograph is a genuine inconvenient truth for 97% of scientists.

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    Neville

    I’m sure there’d be thousands of years of coral bleaching during the much WARMER HOLOCENE CLIMATE OPTIMUM.
    In fact at the end of the HOL OPT sea levels on our coast at Sydney etc were 1.5 metres HIGHER THAN TODAY. That’s 4,000 years ago.
    See their ABC Catalyst Narrabeen man at the link. And not too many Coal plants or SUVs or etc for thousands of years and yet much warmer climate and seas.
    You can watch the video or read the transcript at the link.
    OH and tell any delusional friends or relatives to WAKE UP.

    https://www.abc.net.au/catalyst/narrabeen-man/11010512

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      Kalm Keith

      The fact Earths oceans have fallen 1.2 metres in the last 2,000 years is an undeniable indicator of buildup of ice on the poles.

      The absence of rebound in modern times confirms that temperature is stable and counters the Man Made Climate change hysteria unequivocally.

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        Flok

        Man/woman made climate change. Because man just lies ok, that makes it man made-up climate change. Hence the computer systems were made faster so they can keep up with rate of temperature and CO2 rise graphs.

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    David Maddison

    Another natural phenomenon of the Reef is the Crown of Thorns starfish which “environmental managers” are trying to eliminate, including with autonomous robots, but which has never been proven to be an invasive species.

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    • #
      OriginalSteve

      Maybe the autonomous robots are the invasive species…..

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      Chris

      Oh dear, I was taught at school that the “Crown of Thorns’ Starfish came in ships ballast water from Japan where it was endemic and it was going to kill the reef. I guess it was our CC

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        Deano

        Chris – yes I very vividly remember being taught at primary school in 1971 that the Crown of Thorns starfish was out of control, eating the reef and at the (then) current rate, by 1980 most of the GBR would be lost forever. 1980 was the same year the world would run out of oil too.

        I also have a book about the world-wide disaster that will occur on 1st January 2000 when the Y2K bug hits. Comedians must be annoyed at these amateurs moving in on their patch.

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    clarence.t

    Apparently, coral bleaching is one of those strange things that only happen when someone is there to observe it. 😉

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    • #
      Earl

      The visual equivalent of the auditory “if a tree falls in a forest….”

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      Flok

      Back in 1980 in Europe, there was an incident of chestnut trees die off. It was put down as a cancer of the bark caused by pollution. Moving forward way into the future in 1981, we all had roasted chestnuts around the streets.

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    David Maddison

    Someone made a home made diving bell similar to this…

    https://youtu.be/YNXr-3dfAbs

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      Earl

      Yes and the French are busily (and expensively) trying to make us a fleet of them in South Australia. From all indications your guy might be the lead engineer on that project.

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    STJOHNOFGRAFTON

    The scientific reasons for periodic bleaching of corals is well known to true scientists. Evoking the spirit of anthropogenic global warming as the reason for the bleaching is agenda based scientism.

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    Flok

    Delightful to see that the second opinion on the “current issue” was documented 159 years ago. What other things are locked up in them there histories?

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      Muzza

      ……And that is why the left constantly destroys history – it makes a mockery of their arguments.

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        David Maddison

        Every record has been destroyed or falsified, every book rewritten, every picture has been repainted, every statue and street building has been renamed, every date has been altered. And the process is continuing day by day and minute by minute. History has stopped.

        George Orwell, Nineteen Eighty Four

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          OriginalSteve

          Thats what communists do.

          They are the rust of modern society.

          They are corrosive,and destroy anything good. They are hyenas.

          Marxism is an anti-human modern heresy, that hates all that is good, Godly and Holy.

          Marx was a paid useful idiot.

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    Chris

    Beautiful lithograph, delicate and detailed drawings and typical of the muted colours used by artists of that era. Australian paintings were also painted in those muted tones and took it fifty/ sixty years of paintings before they adapted to the Australian light our pure colours and our unique blue-grey bush.

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    Ken

    If warmer water due to global warming is supposed to be the problem with coral bleaching can someone explain why all the coral reefs closer to the equator are not all dead by now. The water temperatures in those areas are 3 to 4 degrees C warmer than the typical temperatures at the GREAT BARRIER REEF.
    Water temperatures along the GBR, south to north, even vary by about 3 degrees C.

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    Ronin

    The observed increase of ‘bleaching’ apparently got started in the 1960’s when SCUBA gear became readily available.

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      Serp

      Lloyd Bridges and the producers of Sea Hunt are to blame then.

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      John R Smith

      No,
      coral bleaching can be reconstructed from ice cores and tree rings.
      Down to the square foot.
      So it didn’t happen until the industrial age.
      Science.

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    clarence.t

    Reconstruction of GBR bleaching

    https://www.frontiersin.org/articles/10.3389/fmars.2018.00283/full

    “The 1890 and 1750 decades were notable for unusually high bleaching frequencies “

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    TdeF

    The sheer cheek and absurdity of arguing that we are the custodians of the world’s climates is only challenged in the argument that we are the custodians of the largest living object visible from space.

    Sure men have landed on the moon. No one I know personally, but we humans have done it. Now we are the rulers of the planet our engines are clogging the world with CO2 ’emissions’ as if CO2 is an industrial pollutant on a grand scale and we have to control CO2 levels. No one even hints that we cannot. And if a hundred trillion dollars is required, we will just have to spend it.

    You see our CO2 increases CO2 in the air because it refuses to dissolve in water. And the extra CO2 stops backradiation so we are all going to fry and it has heated the air which has somehow heated the water around the Great Barrier Reef and that has produced the first bleaching in history. We know this.

    But what if it is all just natural? What if CO2 is not pollution but the one gas which can capture sunlight and produce life, all life on earth? What if the world really needs more CO2 to feed the extra 6 billion people from the 20th century?

    You would think that with thousands of failed predictions people would believe their own eyes, but in a cult, that seems impossible. So coral bleaching is natural? Who would have thought that? And the crown of thorns starfish has been around for millenia too? Amazing.

    It’s all ours because we live near it. China however thinks we should move and they will come and look after it for us. And all those farms and that huge living space and all that lovely coal, iron ore and those lobsters.

    So now the UN has decided we are bad parents, bad custodians, racists and polluters and we may have to go home. Really?

    In a Nuclear world, this is warfare in slow motion. Lies for the gullible. The Wuhan virus was just the first volley.

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      TdeF

      The increase in ‘world temperature’ has been given as 1.5C in 150 years, since the end of the “Little Ice Age” in fact.

      But the bleaching is a recent event of relatively short duration.

      I cannot keep up with this but has anyone actually explained how an increase of 0.1C in a decade can produce a sudden bleaching event 140 years later? Or even how CO2 warms the air so slowly but warms part of the oceans much faster? And of course that this is not a common event, which is presumed?

      Does anyone at JCU actually try to explain any of this? After all, they receive their hundreds of millions to be experts on the Reef. But how can we be sure they are not just making it up, like their former researcher who is no longer with them? Or his PhD student who was caught as well?

      JCU should be in the first line of defence for Australia. Not part of the attack on our country and our farmers. Defund the lot or at the very least put in a Board and Vice Chancellor who does not persecute scientists for daring to tell the truth.

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    Bass Strait was dry land until about 6000 years ago, and Kangaroo Island and the various island archipelagos off the Western Australian coast were connected to the Australian mainland. What was the state of the now Great Barrier Reef then? Certainly no industrial coal fired power plants then.

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    Serp

    Were we to cut the knot and begin issuing mining permits for our bits of the reef the CCP would become our friend again before the ink was dry.

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      TdeF

      And their research (fishing) boats would appear by magic, as quickly as the fish and crabs and lobster disappeared.

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    David Maddison

    This paper analyses coral core samples to analyse bleaching events back to 1620.

    https://www.frontiersin.org/articles/10.3389/fmars.2018.00283/full

    Mass coral bleaching events during the last 20 years have caused major concern over the future of coral reefs worldwide. Despite damage to key ecosystem engineers, little is known about bleaching frequency prior to 1979 when regular modern systematic scientific observations began on the Great Barrier Reef (GBR). To understand the longer-term relevance of current bleaching trajectories, the likelihood of future coral acclimatization and adaptation, and thus persistence of corals, records, and drivers of natural pre-industrial bleaching frequency and prevalence are needed. Here, we use linear extensions from 44 overlapping GBR coral cores to extend the observational bleaching record by reconstructing temperature-induced bleaching patterns over 381 years spanning 1620–2001. Porites spp. corals exhibited variable bleaching patterns with bleaching frequency (number of bleaching years per decade) increasing (1620–1753), decreasing (1754–1820), and increasing (1821–2001) again. Bleaching prevalence (the proportion of cores exhibiting bleaching) fell (1670–1774) before increasing by 10% since the late 1790s concurrent with positive temperature anomalies, placing recently observed increases in GBR coral bleaching into a wider context. Spatial inconsistency along with historically diverging patterns of bleaching frequency and prevalence provide queries over the capacity for holobiont (the coral host, the symbiotic microalgae and associated microorganisms) acclimatization and adaptation via bleaching, but reconstructed increases in bleaching frequency and prevalence, may suggest coral populations are reaching an upper bleaching threshold, a “tipping point” beyond which coral survival is uncertain.

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      TdeF

      As Charles Darwin proposed, coral keeps growing as mountains keep sinking. It was the only explanation for coral atolls.
      This was confirmed when the American army drilled Bikini atoll and found the coral was over 3km deep.

      Many whole islands are actually solid coral mountains in very deep water as high as the Rocky mountains. The reefs are not some fragile ecosystem but a gigantic long term development which has survived monumental changes over very long periods while Australia has been aware of the Great Barrier Reef only since 1770.

      To suggest that it is now all so tender and fragile beggars belief. Of course it is cooincident with the desire to find industrial pollution and the ravages of man, but the idea that we are inconsequential seems far fetched. We are the newly appointed custodians of the Reef. All 1,400 miles of it. The ocean temperature varies by degrees from one end to the other of this North/South mountain range of coral. But if bleaching occurs, it must be our fault. There is no other explanation.

      We will put it with the 250,000 Caribou who were lost to Climate Change in Canada. But found weeks later. Or the missing thousands of Polar Bears killed by Climate Change and vanishing sea ice and are now in record populations with sea ice at perfectly average levels. All Climate Change.

      The whole idea that every event on the planet is environmental vandalism is ridiculous and based on a strange cult of science megalomania, from heat waves to freezing weather to bushfires and ocean temperatures. But the language of Climate Change means that everyone is at fault. And we argue science without realizing that there is no science involved.

      Better to confess. Yes, I personally bleached the Great Barrier Reef. At night. When no one was looking.

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    ChrisG

    Valerie Taylor says that there was a lot of bleaching in 1965. When they (Ron and Valerie) visited the reef in the early 1970’s the reef had recovered. They are a reliable source on the state of the GBR in the 1960s.

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    CHRIS

    Coral reefs are dynamic living organisms, which have been fluctuating for billions of years (just like any other lifeforms). I’ve always thought that the primary driver of coral reef existence is the PH of the surrounding waters. The reefs are sensitive to changes in PH, and can die or survive depending on this. The latest nonsense that AGW is killing off the reefs is just another lie.

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