Archives par mot-clé : Corals

The State of the Great Barrier Reef 2024(.pdf)

by P. Ridd, Mar 2204, in AustralianEnvironmentFoundation


Table of Contents
Chapter 1: What is the Great Barrier Reef? 4
Chapter 2: The Great Barrier Reef and its coral: The Data. 11
2.1 The area and number of coral reefs on the Great Barrier Reef 11
2.2 Coral Cover: the amount of coral on the Great Barrier Reef. 11
2.3 Coral growth rates (calcification) 19
Chapter 3: Hot-water ‘bleaching’ on the Great Barrier Reef 23
3.1 Introduction 23
3.2 Are bleaching events a new phenomenon? 23
3.3 Corals and their algal friends. 25
3.4 Bleaching is not usually lethal: it is a survival strategy. 27
3.5 Analysis of past GBR bleaching events. 29
3.6: Excuses for Failed Bleaching Predictions 31
3.7 Corals Like it Hot. 33
Chapter 4: Impact of agriculture on coral 35
4.1 Introduction. 35
4.2 Water flushing time of the GBR. 36
4.3: Nutrient ‘pollution’. 38
4.4 Sediment ‘pollution’. 42
4.5 Pesticides. 49
Chapter 5: Stretching the GBR to the coast. 54
5.1 Introduction. 54
5.2 Inshore Reefs. 54
5.3 Mangrove Swamps. 61
5.4 Seagrass beds. 63
5.5 Coastal Freshwater ecosystems. 68
5.6 Importance of Coastal ecosystems to the Great Barrier Reef. 69
Chapter 6 Summary and conclusions 71
Appendix Usefulness of coral cover measurements. 74
About the Author 79
Acknowledgments

The Great Barrier Reef could Die This Year?

by E. Worrall, Feb18, 2024 in WUWT


 

The Great Barrier Reef is in no danger of dying, at most it will change location a little. The reef is composed of an organism which has survived for at least 200 million years, through unimaginably catastrophic global extinction events and disasters, including the asteroid which killed the dinosaurs.

The reason that coral is so good at surviving great upheavals is that while adult coral is immobile, coral spawn is immensely mobile.

Every so often corals spawn. Corals produce immense clouds of microscopic eggs and sperms, which germinate into highly mobile microscopic coral larvae which seek out new places to colonise.

The Great Barrier Reef itself has moved location countless times over the millennia, the reef has only been at its current location for a few thousand years. Some Australian shorelines are composed of coral which lived thousands of years ago, during the Holocene Optimum, when the sea level was significantly higher than today. The Great Barrier Reef had and has no trouble changing location when climate change impacts sea conditions, such as when the world cooled after the end of the Holocene Optimum, and the sea waters retreated to today’s level.

And in fact, Australian coral coverage hit a record high a record high in 2022 – as an organism which is responsive to conditions, coral cover fluctuates wildly when conditions change.

2 More New Studies Undermine Alarmist Claims That Corals Are Harmed By Warming

by K. Richard, Dec 21, 2023 in NotricksZone


Warmer sea surface temperatures are associated with coral growth, not decline.

According to a new study, coral growth was slow during the ~1°C colder Little Ice Age (LIA), but grew rapidly as sea surface temperatures (SSTs) warmed after 1850. Warmth is associated with coral growth, whereas colder SSTs are linked to growth rate decline.

“The average growth rate of four colonies living in the LIA is 0.87 ± 0.11 cm/yr, which is significantly (t-test, p < 0.0001) lower than the colonies in the 20th century [1.23 ± 0.22 cm/yr].”

“The observed low average growth rates during the LIA can be explained by the ~1°C lower temperature.”

Ocean pH levels were as low or lower (more “acidified”) than recent decades during the LIA (e.g., 1500s to 1700s CE), suggesting that the atmospheric CO2 levels are not an ocean pH variability determinant. In fact, the authors point out that anthropogenic CO2 can only ever affect pH variability by 0.05 of a unit over centuries, whereas natural variations in pH units can reach 0.1 to 0.3 within a decade or less.

Pacific coral reef shows historic increase in climate resistance

by Newcastle University, Aug 22, 2023 in EurekAlert


Coral reefs in one part of the Pacific Ocean have likely adjusted to higher ocean temperatures which could reduce future bleaching impacts of climate change, new research reveals.

A Newcastle University-led study focused on the Pacific Island nation of Palau and has shown that historic increases in the thermal tolerance of coral reefs are possible. The results demonstrate how this capacity could reduce future bleaching impacts if global carbon emissions are cut down.

Drawing on decades of field observations, the scientists modelled many possible future coral bleaching trajectories for Palauan reefs, each with a different simulated rate of thermal tolerance enhancement. They found that if coral thermal tolerance continues to rise throughout the 21st century at the most-likely historic rate, significant reductions in bleaching impacts are possible.

Published in the journal, Nature Communications, the results affirm the scientific consensus that the severity of future coral bleaching depends on carbon emissions reductions. High-frequency bleaching can be fully mitigated at some reefs under low-to-middle emissions scenarios where, for example, the Paris Agreement commitments are fulfilled. However, such bleaching impacts are unavoidable under high emissions scenarios where society continues to rely on fossil-fuelled development.

Study lead author, Liam Lachs, is a part of Newcastle University’s Coralassist lab. “Our study indicates the presence of an ecological resilience to climate change, yet also highlights the need to fulfil Paris Agreement commitments to effectively preserve coral reefs,” Lachs said. “We quantified a natural increase in coral thermal tolerance over decadal time scales which can be directly compared to the rate of ocean warming. While our work offers a glimmer of hope, it also emphasises the need for continued action on reducing carbon emissions to mitigate climate change and secure a future for these vital ecosystems.”

Study co-author, Dr James Guest, of Newcastle University’s School of Natural and Environmental Sciences, added: “We know that coral reefs can increase their overall thermal tolerance over time by acclimatisation, genetic adaptation or shifts in community structure, however we know very little about the rates at which this is occurring. This study uses data from a remote Pacific coral reef system and estimates the rate of increase in tolerance since the late 1980s. The results provide some hope that reefs can keep up with increasing temperatures, but only if strong action is taken on climate change.”

This study was the result of a collaborative visit the lead author undertook in 2021 to work with Professor Simon Donner’s Climate and Coastal Ecosystems Laboratory at the University of British Columbia, Canada. “This study shows the potential for some coral reefs to become more resilient to future climate change-fuelled heat waves,” Prof. Donner said. “That resilience, however, can also come at a cost, in terms of reduced reef diversity and growth. Without sharp cuts in greenhouse gas emissions over the next two to three decades, the reefs in the Pacific won’t provide the resources and protection from waves that Pacific peoples have depended upon for centuries.”

 

Continuer la lecture de Pacific coral reef shows historic increase in climate resistance

World’s Coral Reefs Not Declining, New Paper Reveals

by Dr. B. Peiser, Feb 8, 2023 in ClimateChangeDispatch


A new paperpublished by the Global Warming Policy Foundation refutes alarmist claims about the state of the world’s coral reefs.

According to the author, eminent reef scientist Peter Ridd, the official data show no signs of any long-term trends in reef health. [emphasis, links added]

Indeed, the best records – for Australia’s Great Barrier Reef – suggest that coral cover is at record highs.

Dr. Ridd said:

“The public is constantly told that reefs are being irreparably damaged by global warming, but bleaching events, about which there is so much doom-mongering, are simply corals’ natural response to changes in the environment. They are an extraordinarily adaptable lifeform, and bleaching events are almost always followed by rapid recovery.

Dr. Ridd suggests that rather than being seen as under threat from climate change, corals should actually be recognized as one of the organisms least likely to suffer harm in a warming world.

“Corals get energy from a symbiotic relationship with various species of algae. When environmental conditions change, they [coral] can rapidly switch to a different species that is better suited to the new conditions. This shapeshifting means that most setbacks they suffer will be short-lived.”

Dr. Ridd says that the real risks to reefs come from overfishingand pollution.

The GWPF invited responses to this paper from authors likely to dissent from its conclusions. None of the authors who were contacted accepted this invitation.

Peter Ridd: Coral in a Warming World: Causes for Optimism (pdf)

The Great Barrier Reef Is Doing Great; People Should Know

by P. Ridd, Aug 11, 2022 in CO2Coalition


Australia’s Great Barrier Reef (GBR) is, well, great. But the popular media won’t report this good news, so I will.

The GBR is made up of approximately 3,000 reefs covering an area nearly the size of California off Australia’s eastern coast. The condition of its coral is frequently referenced as an indicator of the reef’s health, regularly in the context of the supposed damage global warming is doing to the planet.

The reef now has more coral than any time since records began in 1986, according to  the Australian Institute of Marine Science (AIMS). There is roughly 20 percent more coral on the GBR than last year, which itself equaled a previous record year. All three major regions of the reef now have excellent coral cover and AIMS states that two regions are at record breaking high levels.

As of the latest 2022 survey of the GBR, coral covered 34 percent of the seabed, double the lowest coverage recorded in 2012. There are many types of ecosystem on reefs other than coral – 34% is a remarkably high number.

This coral health exists despite four supposedly massively destructive and unprecedented bleaching events striking parts of the reef since 2016 – all allegedly due to climate change and one as recently as this year. Coral reefs typically take five to 10 years to recover from major damage, so how can GBR be enjoying such good health this soon? Is it possible that reef-science institutions exaggerated the damage in the first place to advance the global warming narrative? Perhaps.

Latest Survey of ‘Coral Cover’ Fundamentally Unscientific

by J. Marohasy, Aug 11, 2022 in WUWT


According to the latest Australian Institute of Marine Science report, there is record coral cover at the Great Barrier Reef. Yet this is less than 30 percent at about half of the reefs surveyed.

The relatively low percentage cover is because only the reef perimeter is surveyed by AIMS, which is the equivalent of reporting on the population of Sydney after skirting around the outer suburbs.

Such a method (skirting around the outer suburbs) would give no indication of population trends in more densely populated inner-city areas. And so the latest AIMS report gives no indication of coral cover at reef crests, which for all we know given the methodology underpinning this latest survey, may have collapsed entirely across the Great Barrier Reef.

We cannot know.

Furthermore, despite advances in both underwater and aerial drone mapping, which could provide automated quantitative assessments by habitat with photographic and/or visual records, AIMS persists with a method that involves towing an observer who guestimates coral cover.

Their method is subjective and archaic. It is not scientific.

My early career was spent as a field biologist in Africa. If I had submitted the AIMS survey method as the intended survey method for any one of the many insect species that I monitored, my supervisors would have rejected it. Whether attempting to monitor changes in the population of an insect species, number of people in a city, or hard coral cover at the Great Barrier Reef, there are certain factors that need to be considered if the method is to be considered scientific and therefore reliable.

Key deficiencies in the current AIMS long-term monitoring program include:
1. Conclusions are drawn about overall coral cover at each reef without ever measuring coral cover at key habitats (E.g. at the reef crest).
2. Variability in coral cover is never quantified by habitat type (E.g. reef crest versus back lagoon).
3. The area surveyed at each reef (defined by AIMS as total ‘reef perimeter’ measured as sum of manta tows) incorporates results from different habitats, and as a consequence it is doubtful that the sample plan is adequate in terms of number of replications (manta tows) per treatment (habitat) at each reef perimeter.
4. Numerical values represent subjective guesses.
5. There is no photographic or video record enabling quantification of the accuracy of the guesses.

Sorry, CNN, Great Barrier Reef Is Setting Records, Fearmongering Won’t Work

by H.S. Burnett, Aug 7, 2022 in WUWT


A new report from the Australian Institute of Marine Science (AIMS) shows the Great Barrier Reef (GBR) set new records for extent this year. Sadly, in a story titled, “Parts of Great Barrier Reef record highest amount of coral in 36 years,” CNN tried to turn this good news contained in the headline into a climate cautionary tale.

According to AIMS’ annual report the northern and central regions of the 2,300 km GBR ecosystem have the most coral since the surveys began 36 years ago. As CNN notes, AIMS survey of 87 sections of the GBR found that between August 2021 and May 2022, average hard coral cover in the upper region and central areas of the reef increased by around one third. AIMS CEO Dr. Paul Hardisty told CNN that the report shows the GBR can “recover from mass bleaching and outbreaks of crown-of-thorns starfish that feed on coral.”

One could be forgiven for missing this good news since CNN spent just a few paragraphs discussing the GBR’s expansion. More than two thirds of CNN’s story talked about the threat posed to the GBR from recent bleaching events purportedly driven by climate change. CNN’s story largely ignored the fact that most of the GBR’s coral colonies impacted by bleaching had recovered, as the AIMS’ report documents.

In a press release from the Global Warming Policy Foundation (GWPF) commenting on the AIMS report its director, Benny Peiser, Ph.D., said, “This is just the latest example of empirical data making a mockery of the catastrophists. For how much longer do they think they can get away with it?”

“In recent years, the media around the world has been reporting coral bleaching events in increasingly apocalyptic terms,” Ridd said in the GWPF’s press release. “This data proves that they are simply scaremongering.”

AIMS’ annual survey confirms what previous posts on Climate Realism have shown, corals in the GBR and around the world are more adaptable than climate alarmists claim.

The evidence suggests, contrary to CNN’s fearmongering, climate change does not threaten to decimate the GBR or other coral reefs around the world. That’s something people around the globe can be thankful for.

The GWPF recently released a study discussing the positive health of coral reefs in general, by Peter Ridd, Ph.D., a long-time researcher on the GBR and coral reefs.

CNN Pushes Coral Apocalypse As Great Barrier Reef Shows Record Growth

by H.S. Sterling, Aug 5, 2022 in ClimateChangeDispatch


A new report from the Australian Institute of Marine Science (AIMS) shows the Great Barrier Reef (GBR) set new records for extent this year.

Sadly, in a story titled “Parts of Great Barrier Reef record highest amount of coral in 36 years,” CNN tried to turn this good news contained in the headline into a climate cautionary tale. [bold, links added]

According to the AIMS annual report, the northern and central regions of the 2,300 km GBR ecosystem have the most coral since the surveys began 36 years ago.

As CNN notes, an AIMS survey of 87 sections of the GBR found that between August 2021 and May 2022, average hard coral cover in the upper region and central areas of the reef increased by around one-third.

AIMS CEO Dr. Paul Hardisty told CNN that the report shows the GBR can “recover from mass bleaching and outbreaks of crown-of-thorns starfish that feed on coral.”

One could be forgiven for missing this good news since CNN spent just a few paragraphs discussing the GBR’s expansion.

More than two-thirds of CNN’s story talked about the threat posed to the GBR from recent bleaching events purportedly driven by climate change.

CNN’s story largely ignored the fact that most of the GBR’s coral colonies impacted by bleaching had recovered, as the AIMS report documents.

In a press release from the Global Warming Policy Foundation (GWPF) commenting on the AIMS report its director, Benny Peiser, Ph.D., said, “This is just the latest example of empirical data making a mockery of the catastrophists. For how much longer do they think they can get away with it?”

The GWPF recently released a study discussing the positive health of coral reefs in general, by Peter Ridd, Ph.D., a long-time researcher on the GBR and coral reefs.

..;

The Great Barrier Reef Is Strong, So Stop The Scare Campaign

by  P.  Ridd, Aug 5, 2022 in ClimateChangeDispatch


The latest data on the coral cover on the Great Barrier Reef, produced by the Australian Institute of Marine Science, should be a cause for celebration.

Church bells should be ringing and children given a day off from school. AIMS says two of the three main regions of the reef are at record-breaking high levels. [bold, links added]

The other region is at record-equaling levels (once uncertainty margins are taken into account).

AIMS, which has been releasing data on the reef every year since 1985, does not give the aggregate of coral cover for the entire reef; it stopped doing that in 2017.

So I have done it for AIMS, and the reef as a whole is at record high levels.

This result is proof that many scientific institutions have been misleading the public about the state of the reef.

They claimed we had four devastating and unprecedented bleaching events since 2016.

So much bleaching, death, and destruction has supposedly never happened before and is because of climate change – and now we have a record-high coral cover.

Official data confirms reef in rude good heath

by P. Homewood, Aug 4 , 2022 in NotaLotofPeopleKnowThat


Official data released today reveals that Australia’s Great Barrier Reef is in excellent health, with coral cover reaching record levels for the second consecutive year.

The increase will be surprising to members of the public, who are regularly hit with scare stories about coral bleaching and false tales about a reef in long-term decline.

A new note, published today by the Global Warming Policy Foundation, explains that the data shows clearly how a handful of coral bleaching events that have affected the reef since 2016 have had very limited impact on overall coral cover.

Record Coral Cover Of Great Barrier Reef Shames Climate Alarmists, Media

by P. Ridd, July 23, 2021 in WUWT


The annual data on coral cover for the Great Barrier Reef, produced by the Australian Institute of Marine Science, was released on Monday showing the amount of coral on the reef is at record high levels.

Record high, despite all the doom stories by our reef science and management institutions.

Like all other data on the reef, this shows it is in robust health. For example, coral growth rates have, if anything, increased over the past 100 years, and measurements of farm pesticides reaching the reef show levels so low that they cannot be detected with the most ultra-sensitive equipment.

This data is good news. It could hardly be better. But somehow, our science organizations have convinced the world that the reef is on its last legs. How has this happened?

Fishy Business: Alleged Fraud over Ocean Acidification Research, Reversal on Coral Extinction

by R. Alexander, June 28, 2021 in ScienceUnderAttack


In the news recently have been two revelations about the sometimes controversial world of coral reef research. The first is fraud allegations against research claiming that ocean acidification from global warming impairs the behavior of coral reef fish. The second is an about-face on inflated estimates for the extinction risk of Pacific Ocean coral species due to climate change.

The alleged fraud involves 22 research papers authored by Philip Munday, a marine ecologist at JCU (James Cook University) in Townsville, Australia and Danielle Dixson, a U.S. biologist who completed her PhD under Munday’s supervision in 2012. The fraud charges were made in August 2020 by three of an international group of mostly biological and environmental scientists, plus the group leader, fish physiologist Timothy Clark of Deakin University in Geelong, Australia. The Clark group says it will publicize the alleged data problems shortly.

The research in question studied the behavior of coral reef fish in slightly acidified seawater, in order to simulate the effect of ocean acidification caused by the absorption of up to 30% of humanity’s CO2 emissions. The additional CO2 has so far lowered the average pH – a measure of acidity – of ocean surface water from about 8.2 to 8.1 since industrialization began in the 18th century.

Munday and Dixson claim that the extra CO2 causes reef fish to be attracted by chemical cues from predators, instead of avoiding them; to become hyperactive and disoriented; and to suffer loss of vision and hearing. But Clark and his fellow scientists, in their own paper published in January 2020, debunk all of these conclusions. Most damningly of all, the researchers find that the reported effects of ocean acidification on the behavior of coral reef fish are not reproducible – the basis for their fraud allegations against the JCU work.

Peter Ridd: It’s the science that’s rotten, not the Great Barrier Reef

by P. Homewood, Dec 7, 2020 in NotaLotofPeopleKnowThat


 

The International Union for Conservation of Nature has released its latest report on the state of the Great Barrier Reef. It has turned up the volume by one notch, claiming the threat to the reef has gone from “significant concern” to “critical”. It blames climate change, agricultural pollution, coastal development, industry, mining, shipping, overfishing, disease, problematic native species, coal dust — you name it, it is killing the reef.

But the report is just a rehash of old, mostly wrong or misleading information produced by generally untrustworthy scientific institutions with an activist agenda and no commitment to quality assurance.

It is remarkable that the world has been convinced that one of its most pristine ecosystems is on its last legs. Part of the problem is that, being underwater and a long way from the coast, very few people visit the reef. The truth is hidden. Those of us in North Queensland living adjacent to the reef, and tourists from elsewhere, can report the water is iridescent clear blue and totally unpolluted. The fish and coral are fabulous.

Measuring Old Corals & Coral Reefs (Part 1)

by J. Marohasy, Nov 29, 2020 in WUWT


Fundamental to science is measurement. It is a way of objectively assessing something, anything, even the state of a coral reef, even of an individual coral. Historically coral growth rates were measured by coring the really old massive Porites.

Like tree rings in temperate forests, the massive old Porites can be cored to see the banding and from this it is possible to calculate coral calcification rates which are a measure of the growth rate of individual corals.

Peter Ridd has been asking for some quality assurance of so many of the measurements relating to Great Barrier Reef health, including coral growth rates. Key Australian institutions have responded by stonewalling, and in the case of James Cook University, actually sacking him. After two rounds in the federal courts his appeal against his dismissal is finally going to the High Court of Australia, with the next hearing probably in February 2021. While the lawyers are preoccupied with Peter’s rights, or otherwise, to academic freedom and freedom of speech, my concern is whether Peter is actually telling the truth when he says that the Great Barrier Reef is resilient and definitely not dying from coral bleaching, though there is a problem with the integrity of the science.

 

Half the Reef destroyed but they won’t release the data

by JoNova, Oct 16, 2020


The future of the entire 350,000 km2 Great Barrier Reef hangs in the balance — as the coralapocalypse has wiped out 50% of the coral in just 25 years. Lordy! If only we’d built some off-shore wind farms on the reef to protect it! We could cover whole islands with solar panels? What are we thinking!

But as Peter Ridd points out, AIMS (The Australian Institute of Marine Science) surveys around 100 reefs every year — and for the last 35 years — and they find things are roughly the same. See the graph below.

Somehow Terry Hughes — and the Centre of Excellence for Integrated Coral Reef Studies — gets up to $4 million each year to report on the reef but won’t release the data behind the mass media campaign.

The ABC — which gets nearly $3 million dollars every single day — can’t even pick up the phone to interview AIMS or Peter Ridd and ask one hard question of Terry Hughes’ “Excellent” centre. (We all know why they had to put the word “excellence” in the title, it was the only way the word would ever be used to describe an activist group pretending to be scientists.)

And we all know that if anyone at James Cook University (JCU) has any doubts about the quality of the output from the “Excellent” centre they won’t be saying a word or they’ll get sacked like Peter Ridd did.

JCU — still supporting junk science and ignoring that other case of potential fraud?

Claim: Ocean acidification causing coral ‘osteoporosis’ on iconic reefs

by WOODS HOLE OCEANOGRAPHIC INSTITUTION, August, 28, 2020 in WUWT


Scientists have long suspected that ocean acidification is affecting corals’ ability to build their skeletons, but it has been challenging to isolate its effect from that of simultaneous warming ocean temperatures, which also influence coral growth. New research from the Woods Hole Oceanographic Institution (WHOI) reveals the distinct impact that ocean acidification is having on coral growth on some of the world’s iconic reefs.

 

IMAGE: WHOI SCIENTIST ANNE COHEN (LEFT) AND MIT-WHOI JOINT PROGRAM STUDENT NATHAN MOLLICA EXTRACT CORE SAMPLES FROM A GIANT PORITES CORAL IN RISONG BAY, PALAU. view more CREDIT: PHOTO BY RICHARD BROOKS, LIGHTNING STRIKE MEDIA PRODUCTIONS, PALAU.

In a paper published Aug. 27, 2020, in the journal Geophysical Research Letters, researchers show a significant reduction in the density of coral skeleton along much of the Great Barrier Reef–the world’s largest coral reef system–and also on two reefs in the South China Sea, which they attribute largely to the increasing acidity of the waters surrounding these reefs since 1950.

“This is the first unambiguous detection and attribution of ocean acidification’s impact on coral growth,” says lead author and WHOI scientist Weifu Guo. “Our study presents strong evidence that 20th century ocean acidification, exacerbated by reef biogeochemical processes, had measurable effects on the growth of a keystone reef-building coral species across the Great Barrier Reef and in the South China Sea. These effects will likely accelerate as ocean acidification progresses over the next several decades.”

Roughly a third of global carbon dioxide emissions are absorbed by the ocean, causing an average 0.1 unit decline in seawater pH since the pre-industrial era. This phenomenon, known as ocean acidification, has led to a 20 percent decrease in the concentration of carbonate ions in seawater. Animals that rely on calcium carbonate to create their skeletons, such as corals, are at risk as ocean pH continues to decline. Ocean acidification targets the density of the skeleton, silently whittling away at the coral’s strength, much like osteoporosis weakens bones in humans.

Reefs’ Neon Colors A Defense Against Coral Bleaching

by B. Bruno,  May 22, 2020 in ClimateChangeDispatch


Some coral reefs are adapting to warming ocean temperatures by making their own sunscreen in the form of bright neon colors — a strategy that invites coral animals to return to reefs and is seen as a critical adaptation to maintain healthy coral reefs around the world.

In a study published Thursday in the journal Current Biology, researchers at the University of Southampton detail a series of controlled laboratory experiments they conducted at their coral aquarium facility.

In the experiments, “colorful” coral bleaching events cause coral to produce a layer of vibrant sunscreen which encourages the coral animals vital to a mutually beneficial “symbiosis” relationship to return to coral habitats they abandon due to the effects of warming oceans.

The colorful adaptation could prove vital for overcoming the fatal coral bleaching incidents that have threatened coral reefs worldwide.

But the colorful coral bleaching – rather than the white skeleton exposure of common coral bleaching events – is believed to take place due to mild ocean warming or disturbances in their nutrient environment, rather than extreme events.

Colorful bleaching occurred between this past March and April in some areas of the Great Barrier Reef, suggesting some patches of the world’s largest reef system may have better recovery prospects than others.

Coral Catastrophes Imagined

by Jennifer, April 10, 2020 in WUWT


From Jennifer Marohasy’s Blog

April 10, 2020 By jennifer

Exactly one year ago yesterday, I was getting off a train in Proserpine, looking to pickup a hire car to drive to Bowen. I wanted to know if the coral there was all dead, or not. Bowen is a coastal town in North Queensland, not far from Abbott Point that is the coal terminal for the controversial Adani coal mine.

Judge Salvador Vasta had earlier that week handed down his findings regarding the sacking of Peter Ridd. He had exonerated Ridd and explained that James Cook University had wrongly sacked him.

Some claim that it all came to a sorry end for Ridd because he dared to question the consensus of scientific opinion concerning the health of the Great Barrier Reef – particularly the impact of global warming. The university claimed it was because he had become ‘un-collegial’ and did not follow various directives while disclosing confidential information.

These issues were argued in the Federal Circuit Court in Brisbane a month earlier, in March 2019. Very few people realized that at the heart of the case were a couple of what might be best described as fake-news photographs promoted by Terry Hughes.

This is the same Terry Hughes who is now claiming that 60%* of the Great Barrier Reef has been bleached, and that this is an extraordinary catastrophe for which we should all be ashamed.

If Peter Ridd had become un-collegial and disclosed confidential information, it was because he was fed-up with the fake news. As Ridd wrote in chapter 1 of the book that I edited three years ago, a chapter entitled ‘The Extraordinary Resilience of Great Barrier Reef Corals, and Problems with Policy Science’:

New Study: Coral Reefs Thrive Near Acidic Waters (pH ~6.0) Where Seafloor Vents Emit Up To 95,000 ppm CO2

by K. Richard, March 30, 2020 in NoTricksZone


Though it’s believed the 130 ppm increase in atmospheric CO2 concentration since 1750 has caused the ocean waters to “acidify”, on a daily basis 50-380°C metallic acid enriched by CO2 concentrations reaching 60,000 to 95,000 ppm pours through seafloor vents. Nearby coral reefs “thrive” in these high-CO2 conditions.

50 times more CO2 in the oceans than in the atmosphere

Though many believe humans are “acidifying” the oceans by burning fossil fuels and emitting CO2, the ability of humans to impact the oceanic CO2 concentration is already compromised by the observation that the ocean waters contain about 50 times more CO2 (38,000 vs. 750 PgC) than the atmosphere does (North et al., 2014).

Coral tells own tale about El Niño’s past

by Rice University, March 27, 2020 in WUWT


HOUSTON – (March 26, 2020) – There is no longer a need to guess what ocean temperatures were like in the remote tropical Pacific hundreds of years ago. The ancient coral that lived there know all.

A study in Science led by Rice University and Georgia Tech researchers parses the record archived by ancient tropical Pacific coral over the past millennium. That record could help scientists refine their models of how changing conditions in the Pacific, particularly from volcanic eruptions, influence the occurrence of El Niño events, which are major drivers of global climate.

They found the ratio of oxygen isotopes sequestered in coral, an accurate measure of historic ocean temperatures, shows no correlation between estimates of sulfate particles ejected into the atmosphere by tropical volcanic eruptions and El Niño events.

That result could be of particular interest to scientists who suggest seeding the atmosphere with sun-blocking particles may help reverse global warming.

According to Rice climate scientist and primary author Sylvia Dee, previous climate model studies often tie volcanic eruptions, which increase sulfate aerosols in the atmosphere, to increased chances for an El Niño event. But the ability to analyze climate conditions based on oxygen isotopes trapped in fossil corals extends the climatological record in this key region across more than 20 ancient eruptions. Dee said this allows for a more rigorous test of the connection.

“A lot of climate modeling studies show a dynamical connection where volcanic eruptions can initiate El Niño events,” Dee said. “We can run climate models many centuries into the past, simulating volcanic eruptions for the last millennium.

“But the models are just that — models — and the coral record captures reality.”

Coral data that Georgia Tech climate scientist Kim Cobb and her team arduously collected on trips to the Pacific show little connection between known volcanoes and El Niño events over that time. Like tree rings, these paleoclimate archives hold chemical indicators, the oxygen isotopes, of oceanic conditions at the time they formed.

The coral data yields a high-fidelity record with a resolution of less than a month, tracking the El Niño-Southern Oscillation (ENSO) in the heart of the central tropical Pacific.

Climate At A Glance Factchecks–Coral Reefs

by P. Homewood, March 21, 2020 in NotaLotofPeopleKnowThat


Bullet Point Summary:

  • Coral thrive in warm water, not cold water.
  • Recent warming has allowed coral to expand their range poleward, while still thriving near the equator.
  • Coral has existed continuously for the past 40 million years, surviving temperatures and carbon dioxide levels significantly higher than what is occurring today.
  • The primary causes of coral bleaching include oxybenzone (a chemical found in sunscreen), sediment runoff from nearby coastal lands, and cold temperatures like those recorded in 2010 off the Florida coast.
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Short Summary: Coral require warm water, not cold water, to live. Coral cannot live outside of tropical or subtropical waters. (See Figure 1.) As Earth continues to modestly warm, coral are extending their range toward the poles while still thriving at and near the equator. The primary reasons for bleaching events include sediment pollution from nearby coastal lands, chemicals found in sunscreen, and cold temperature events. Coral have existed continuously for the past 40 million years. Coral survived and thrived when temperatures were significantly warmer than they are today.

Figure 1: Coral Reef Locations

Continuer la lecture de Climate At A Glance Factchecks–Coral Reefs