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Coal's formation is a window on an ancient world

The Conversation - Wed, 2016-06-08 06:23
Coal has provided us with some stunning fossils. Bart Bernardes/Flickr, CC BY-NC-ND

As the world moves to combat climate change, it’s increasingly doubtful that coal will continue to be a viable energy source, because of its high greenhouse gas emissions. But coal played a vital role in the Industrial Revolution and continues to fuel some of the world’s largest economies. This series looks at coal’s past, present and uncertain future, starting today with how it’s formed.

Love it or hate it, coal played a crucial role in launching us into the modern world by fuelling the Industrial Revolution. The byproducts of that role were, of course, the rise of greenhouse gases in our atmosphere and dangerous levels of air pollution in the big coal-fuelled cities.

But despite its insidious influence on the climate and our health, coal has a lesser-known positive side to its otherwise dark soul. It has provided us with some stunning fossils.

Geologists have known for centuries that coal is an accumulation of plant material that, once buried in the Earth’s sedimentary layers, gets compressed by gravity into a denser, compact form. Yet, in recent years, scientists have hotly debated the early phases of coal formation.

The discussion hinges on whether coal formed due to the absence of certain organisms that actively break down the woody tissues of dead trees, or whether other non-biological factors were the reason.

Contested origins

Coal starts its cycle of formation with the accumulation of plant material in swamps or bogs. Decaying plant matter that builds up at the bottom of bogs or swamps is called peat. After other sedimentary layers bury the peat deposit, the weight of these sediments builds up and compacts it.

Other chemical and physical processes also alter the peat, including pressures exerted by tectonic forces as continents move and crash into one another. These processes eventually turn the layers of compacted peat into rock we can mine.

Pure black coal, richer in organic carbon and tempered by heat and pressure, is called anthracite. Brown coal, or lignite, is mostly just compressed peat and has more sediment mixed in with plant matter.

Coal has formed as very large deposits at certain times in Earth’s prehistory. So much so that Reverend William Conybeare, the esteemed British geologist of the early 19th century, first named the Carboniferous or “carbon-bearing” period (359 million to 299 million years ago) after the distinctive coal deposits of Britain in his book of 1822.

These great coal swamps formed in what were the Earth’s first great forests. They were home to many varieties of giant amphibians and early reptiles and huge insects, as global oxygen levels were very high at this time.

Scientific treasures from coal: the Iguanodon dinosaur display in Brussels Museum of Natural Sciences. Brussels Museum of Natural Sciences website

For many years, scientists believed that coal formed in such large deposits at these times because certain fungi that helped break down the lignin, or woody tissues, had not yet evolved. The molecular clock estimates for the appearance of these fungi, called Agariomycetes, suggest they should appear in the Permian period (299 million to 252 million years ago), after the formation of the vast Carboniferous coal deposits.

A new theory

But this doesn’t account for the huge amounts of coal that formed in much later geological periods, such as the Cenozoic, over the past 65 million years. And a new study, led by Matthew Nelsen of Stanford University, takes issue with this model, as well as presenting a new hypothesis for coal formation.

The study authors argue that coal formed in the Carboniferous period consists dominantly of plants such as horsetails, or Lycophytes. These trees grew to enormous sizes and their periderm, or outer cuticles of the trunk, lack lignin, so wouldn’t be affected by the absence of lignin-degrading fungi. Their argument points to the biochemical composition of the plants having little to do with how coal accumulates.

The distribution of coal deposits through time is seen in the chart below of the estimated total volume of coal in North America. Large deposits of coal also accumulated during the age of dinosaurs (Mesozoic Era, from 252 million to 66 million years ago) and during the first half of the Cenozoic period (between 66 million and 30 million years ago), well after the predicted first appearance of lignin-degrading fungi.

Terrestrial coal accumulation in North America, through time. Note the large peaks during the Carboniferous ‘C’ and early Cenozoic ‘Pg’. Taken from the paper by Nelsen et al. (2016). Prof. Kevin Boyce, with permission.

The paper argues that tectonic factors are the most likely reason such big coal deposits built up at certain times. Large basins fill up with thick sedimentary piles when continents collide and mountain-building occurs. Some really excellent fossils have been found in such coal deposits, although the acidity of coal often dissolves bones.

The best-preserved fossils are those caught in the cleaner sediments laid down by streams between coal seams. Such fossils are routinely uncovered as part of coal mining. Several of the large fossil amphibians that lived in the Carboniferous swamps have been found this way.

A famous site at Nyrany in the Czech Republic was discovered because the director of the natural history museum there had coal delivered to heat his room. Splitting the coal sometimes yielded well-preserved fossils of early amphibians, so he could add scientifically significant specimens to his collections without leaving his office.

Perhaps the most famous fossils found in a coal mine were uncovered at Bernissart in Belgium. Many skeletons, representing 33 individuals of the large plant-eating dinosaur Iguanodon, were found there in 1878. These skeletons were among the first complete dinosaurs ever found.

Although coal is much maligned because of its byproducts from combustion, the factors responsible for coal accumulation also give us fossil treasures from the past. To stop coal mining would undoubtedly mean many good fossils remain in the ground. But the long-term health of our planet is a bigger priority.

This is the first article in our series on the past, present and future of coal. Look out for others in the coming days.

John will be online for an Author Q&A between 2:30 and 3:30pm AEST today (Wednesday 8 June, 2016). Post any questions you have in the comments below.

The Conversation

John Long receives funding from The Australian Research Council

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Westerners lack education on nuclear disaster risks, expert warns

The Guardian - Wed, 2016-06-08 05:10

Christopher Abbott says orderly evacuation seen during Japan’s Fukushima incident would not work as well in western societies

Western societies would not respond well to a Fukushima-style nuclear disaster due to a lack of public information, a leading disaster expert has warned.

Christopher Abbott said he firmly believed that the public ought to be better educated over the hazards and risks they may face.

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What happened to the UK shale gas report? | Letters

The Guardian - Wed, 2016-06-08 03:56

Janet Russell asks the right question (Letters, May 30). What has happened to the report on shale gas by the UK Climate Change Committee (CCC)? When Professor Cowern and I gave evidence in February, we were assured that the report would be published no later than May. We have also been told unofficially that the CCC has accepted our data on fugitive emissions of methane and that shale gas is two times worse than coal from a climate change perspective. We also submitted a further paper towards the end of March, indicating that over half of the rise in atmospheric levels of methane seen globally since 2007 is due to oil and gas, notably shale extraction in the US, and that this is obscuring the rise in methane emissions from the Arctic. I suppose it would be highly embarrassing for the government if its “dash for gas” was found to be incompatible with our climate change commitments, agreed by the UN but implemented via EU legislation. Embarrassing unless the government accepted the scientific case and announced it was going to abandon fracking and invest in renewables.
Dr Robin Russell-Jones
Stoke Poges, Buckinghamshire

• Join the debate – email guardian.letters@theguardian.com

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UK solar eclipses coal power over month for first time

The Guardian - Wed, 2016-06-08 02:42

Longer days helped solar panels generate 50% more electricity than coal across the whole of May, analysis shows

Solar power in the UK produced more electricity than coal across the whole of May, the first ever month to pass the milestone, according to research by analysts at Carbon Brief. Solar panels generated 50% more electricity than the fossil fuel across the month, as days lengthened and coal use fell. Solar generated an estimated 1,336 gigawatt hours (GWh) of electricity in May, compared to 893GWh output from coal.

Coal was once the mainstay of the nation’s power system but the rapid rise of solar panels and of climate change concerns has seen its use plummet, leading to a series of milestones in recent weeks.

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Bleaching 'devastates' UK tropical reef

BBC - Wed, 2016-06-08 02:21
Up to 85% of the corals in the Chagos Marine Reserve of the British Indian Ocean Territory are estimated to have been damaged or killed in the current global bleaching event.
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Mike Croxford obituary

The Guardian - Wed, 2016-06-08 01:50

My lifelong friend and colleague Mike Croxford, who has died aged 71, was a pioneer of recycling in his native Wales. The Welsh government’s current recycling performance – at 60% it is fourth in Europe – owes much to Mike, who was a founder member of the Zero Waste movement worldwide and of the Zero Waste International Trust.

His interest in recycling began in 1980, while running the Augusta Street youth project in Cardiff. The young people started collecting newspapers to improve their standing among local people and to fundraise to run events for the community. The project turned into the Community Support Anti-Waste Scheme (CSAWS) that in 1986 initiated the first citywide collection scheme in the UK.

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Woman paddleboarding England's canals finds thousands of plastic items

The Guardian - Wed, 2016-06-08 01:33

Lizzie Carr catalogued vast amount of plastic junk clogging 400 miles of waterways as she paddled through during her 22-day journey

A woman who paddled 400 miles up the length of England’s waterways found them choked with thousands of plastic items, from bottles and bags to toys and dummies.

Lizzie Carr completed the 22-day challenge on Sunday with swollen knuckles and more than 2,000 photos of plastic junk she found in canals and rivers from Godalming in Surrey to Kendal in Cumbria.

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Gravity space mission passes big test

BBC - Wed, 2016-06-08 00:06
The Lisa Pathfinder mission, which was designed to demonstrate the technologies needed to detect gravitational waves in space, has been a stunning success, say officials.
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Don't get riled by the AA advising cyclists – save your anger for the Highway Code

The Guardian - Tue, 2016-06-07 21:10

Despite a backlash by some cyclists at the motoring organisation’s Cyclist’s Highway Code, the AA’s new book on cycling isn’t as bad as you might think

When the AA, the UK’s largest motoring organisation, published a Cyclist’s Highway Code on Monday, I thought it seemed like a bizarre but effective way to wind up passionate cyclists such as myself.

I already don’t like the official Highway Code for telling me I “should” wear a helmet and fluorescent clothing to ride around in daylight when studies have concluded neither will make cycling safer for me or the community in which I cycle.

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Green Conservatives call for earlier UK coal power phase-out

The Guardian - Tue, 2016-06-07 20:11

Closing coal plants by 2023 rather than 2025 will cut carbon emissions and air pollution, and boost clean energy projects, Tory thinktank tells government

The UK should close all its coal-fired power stations two years earlier than the government’s pledge of 2025, according to green Conservatives including former energy minister Lord Greg Barker.

The move would not cause the lights to go out, would cut both carbon emissions and air pollution and would boost cleaner energy projects, according to a report from Bright Blue, a thinktank of Tory modernisers.

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The future risk of living on the coast

ABC Environment - Tue, 2016-06-07 18:35
Will beachfront properties become uninsurable before they become uninhabitable?
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Origin of mystery deep-sea mushroom revealed

BBC - Tue, 2016-06-07 18:15
Australian scientists have used genetic material to pinpoint the origin of the deep-sea mushroom, an unusual gelatinous creature first dredged up near Tasmania in 1986.
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Sydney's wild weather shows home-owners are increasingly at risk

The Conversation - Tue, 2016-06-07 16:35

Eastern Australia’s wild weather has left coastal homes teetering on the brink of collapse, and has eroded beaches by up to 50m in parts of Sydney.

Now the attention turns to the clean-up. There are several legal issues for owners of damaged properties, particularly the question of if and how they can be compensated.

While the recent events cannot be attributed directly to climate change, they are certainly consistent with a warming world. Our institutions are ill-prepared for a potential increase in the frequency and severity of such events.

Insurance

Unfortunately, the success of insurance claims for damaged homes in Sydney will depend entirely on the terms of their policies. Some policies don’t cover erosion at all. Some policies only cover it if it occurs within a certain proximity of another insured event (for example, within 48 hours of a named storm event). Some policies also comprehensively exclude coverage for damage caused by actions of the sea.

What’s more, while insurance will cover damage to buildings, policies do not extend to cover damage to or loss of land. This is especially problematic in the case of damage caused by waves and storms, because erosion will often result in loss of land.

Under the traditional law doctrine, where land is lost to erosion, the Crown automatically gains title to the inundated land, without any obligation to pay compensation. So even if a home-owner is insured, they may find themselves with no land to rebuild on.

Legal proceedings

Another potential avenue for home-owners to pursue is proceedings against the relevant local government for negligent approval of development. The success of this type of proceeding is highly speculative – much will hinge upon when the development was approved and how much information on the coastal hazards was available at that time.

Where development was approved decades ago, it may be difficult to prove that a local government was negligent, because of the limited state of knowledge at the time. In the case of more recent development approvals, there may be an argument that a local government had a high level of knowledge of the risk and control of risk information. These are the type of factors a court will look at in assessing negligence.

On the flip side, a court may also find that a landholder knew of and accepted the risk. Negligence proceedings are by no means a guaranteed avenue for landholders to recoup their loss, but are an avenue that Collaroy landholders may be able to explore.

Disaster assistance

Where insurance is not available, and there are no strict legal rights against government, landholders may request disaster relief or assistance from government.

Despite the lack of any legal compulsion to do so, Australian governments have a long history of providing disaster relief to citizens when an extreme weather event causes property damage.

A recent Productivity Commission report estimated that, over the past decade, the federal government spent A$8 billion on post-disaster relief and recovery. State governments spent a further A$5.6 billion.

However, the availability and amount of a payment are not guaranteed. This may depend upon the number of other claims for assistance, and any other demands on government resources. A claim for disaster relief from government may be an option for Collaroy landholders, but many other home-owners are also affected by flooding due to the recent extreme weather – and so potentially there are many other requests for relief.

What should we learn from this event for the future?

While the pictures of houses being lost to the sea in Collaroy are confronting, these images may become more commonplace. The most recent scientific report from the Intergovernmental Panel on Climate Change suggests that, under a business-as-usual scenario, a global sea-level rise in the range of 0.53-0.97m by 2100 is likely.

Even if emissions are immediately reduced, a global sea-level rise of 0.28-0.60m by 2100 is still possible. This will be especially problematic in Australia, with an estimated 711,000 residential addresses located within 3km of the shore and less than 6m above sea level – not to mention the billions of dollars' worth of government infrastructure also located in these regions.

As sea levels rise, some properties may be permanently inundated. Others may be hit by storm surge impacts or erosion, which may be exacerbated by sea-level rise.

If these events continue to attract disaster relief, the financial burden will become too great for governments to bear. Furthermore, government disaster assistance does not solve the more intractable problem of land being lost to the sea.

The pictures from Collaroy should therefore prompt a discussion about how we, as a society, can deal with the potential impacts of coastal hazards on existing developments.

This is a challenging question to answer, but there is an opportunity to address it in a planned and co-ordinated fashion.

The Conversation

Justine Bell-James has previously received funding from the Australian Research Council and the National Climate Change Adaptation Research Facility.

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'Let me outta here!' – amazing picture of a fish trapped inside a jellyfish

The Guardian - Tue, 2016-06-07 15:32

This unlucky fish came unstuck when it was ‘swallowed up’ by a roaming jellyfish in waters off Byron Bay, Australia. The shot was captured by ocean photographer Tim Samuel, who says the fish was still alive and fighting to escape. ‘It was able to propel the jellyfish forward and controlled its movement to an extent. The jellyfish threw it off balance, though, and they would wobble around, and sometimes get stuck doing circles.’

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Massive storms are pumping pollution into our oceans: time to clean up our cities

The Conversation - Tue, 2016-06-07 12:06

The massive storms that have lashed Australia’s east coast over the past few days are not just a threat to lives and property, but also to our marine wildlife.

The increasing urbanisation of our coastlines, and proliferation of impervious surfaces, has meant that up to 80% of stormwater now runs rapidly into a dense underground network of drains.

These drains act like an expressway for pollution and debris in our cities, roads, gutters and gardens, sending a cocktail of contaminants directly into the aquatic ecosystems that lie at the end of the pipe.

Stormageddons

Earlier this year, Newcastle recorded its wettest January day since 1862. In 2015, New South Wales experienced a “once in a century” storm event.

These storms along Australia’s east coast originated mainly from naturally occurring low-pressure systems, which may become less frequent but more severe in the future. Worldwide extreme weather events are becoming more common, with about 18% of heavy precipitation events attributed to global warming.

Australia is not the only country receiving a drenching. Torrential rains have hit Texas twice this year, breaking records in May and unleashing two 100-year storms in less than a week. Louisiana and Mississippi have been placed on flood watch.

Across the Atlantic, Europe is also emerging from receding flood waters, with the River Seine in France at its highest levels since 1910 and southern Germany battered by thunderstorms, hail and flash flooding.

A pollution cocktail

Stormwater is a mixture of rain and any dissolved or solid pollutants carried along with it. The excess water flowing along streets and gutters picks up litter, oil and grease, and metals. Run-off from parks and gardens introduces fertilisers, pathogens, pesticides and soil.

In Sydney Harbour it has been estimated that more than two-thirds of the pollutants entering the waterway do so via stormwater drains, creating hotspots of pollution with concentrations 20 times higher than natural levels. More than 80% of the city’s catchment is covered by concrete, increasing the volumes of stormwater run-off.

When stormwater reaches a waterway it represents a significant ecological risk. Together with international colleagues, we have been investigating the impact of stormwater pollution on ecological communities large and small, including changes to the number of species, nutrient cycling, and the release of toxic compounds such as ammonia, nitrous oxide and hydrogen sulphide.

Mobile animals such as fish and crustaceans may be able to avoid pollution by temporarily moving. But other aquatic organisms such as seaweeds and animals that anchor to rocks are more vulnerable. If they don’t die from the exposure, they may accumulate significant concentrations of pollutants within their bodies.

In stagnant or poorly flushed waterways, the risk of exposure is greater as pollutants tend to linger in the water and become bound to sediments where they act as an ongoing stress.

A big question is what happens when ecosystems are exposed to many different pollutants. Some studies suggest the impacts will be greater than the sum of the individual pollutants.

Building better cities

The solution to stormwater run-off is to build better: to design and construct cities to protect waterways such as rivers, manage stormwater and also make them liveable for people too. This approach is known as water-sensitive urban design.

One example is the large underground water tanks that collect stormwater to be reused for irrigation at Sydney’s Barangaroo Reserve.

You can help at home too by retaining vegetation, installing rainwater tanks, clearing excess leaf litter and debris from guttering and driveways, and reducing the use of pesticides and fertilisers on gardens. Rainwater tanks have proven particularly successful at capturing all stormwater for reuse in toilet flushing and irrigation.

While we need to clean up our waterways, we also need to make sure that enough water and organic matter are flowing through our rivers and into the oceans. Getting the balance right will make for better cities and healthier oceans.

The Conversation

Katherine Dafforn receives funding from the Australian Research Council and Lendlease. She is affiliated with the Sydney Institute of Marine Science.

Emma Johnston receives funding from the Australian Research Council.

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Flood deaths are avoidable: don't go in the water

The Conversation - Tue, 2016-06-07 11:50

The flooding rains that have drenched eastern Australia have tragically left several people dead and several more missing in New South Wales and Tasmania. This is an all-too-common story – flooding rains are a major cause of deaths around the globe.

Since 1994, we have studied the trends and causes of deaths due to natural disasters. Recent research into flood fatalities in Australia from 1900 to 2015 is revealing some important insights.

Our research suggests many of these deaths are avoidable.

How people die in floods

Since 1900, 1,859 people in Australia have died in floods. That’s more than in bushfires and earthquakes, but less than heatwaves, which remain by far Australia’s most deadly natural peril (excluding pandemic diseases). Of these flood deaths, 178 have occurred since 2000.

The majority of deaths have been male (79%), although the proportion of females has increased since the 1960s. Children and adults younger than 29 make up the majority.

Overall, most deaths have occurred in New South Wales and Queensland, although a greater proportion of people die in the Northern Territory compared to the population. Most deaths happen in relative isolation, in flood events that claim either one or two lives.

Most people have died while attempting to cross a bridge, causeway, culvert or road, either on foot or in a vehicle. While most victims were capable of independent action and aware of the flood, the speed and depth of the water took them by surprise.

Of those who were attempting to reach a destination at the time of death, the greatest number were on their way home. Playing in flood water is also a significant cause of death, particularly for children and young adults. More women and children died in floods due to the decisions of others – for example, being a passenger in a vehicle.

Those on foot mostly perished during the daytime, whereas those in vehicles were more likely to die in the evening when visibility is poorer. The majority of fatalities happened within the local area close to where they lived.

Overall, flood deaths have been declining since the early 1960s. This is probably due to investments in flood mitigation and warning systems, and the work of emergency service organisations such as the State Emergency Services. Deaths associated with motor vehicles, however, are on the rise and those associated with four-wheel-drive vehicles have increased over the past 15 years. The large majority of drivers have been men.

Our research has shown that many people simply ignore warnings and road closure signs. In one case in 2015 in NSW, 84% of motorists were observed driving past road closure signs and entering flood waters. Most were men driving four-wheel-drive vehicles.

How can we prepare people?

Our unpublished survey has revealed that Australian emergency managers prefer improving roadside warning signage at causeways, flood warning systems and road design in flood-prone areas.

However, it is clear that current practices are failing and must be complemented with a strategy to inspire behavioural change in the community.

Education programs should be targeted at young males at risk of entering floodwater, and at females and children to raise their awareness so that they may be empowered to influence motorist behaviour.

It is too easy to underestimate the dangers associated with floods. Our vehicles, even four-wheel-drives, do not provide a safe means of crossing flooded roadways. The public must understand that flood waters need to be respected, and be ready to work with authorities to reduce risks posed by flooding to our towns and cities.

See here for the full research report.

The Conversation

Katharine Haynes receives funding from and is affiliated with the Bushfire and Natural Hazard Cooperative Research Centre.

Andrew Gissimg receives funding from the Bushfire and Natural Hazards Cooperative Research Centre.

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The Great Barrier Reef: a catastrophe laid bare

The Guardian - Tue, 2016-06-07 09:54

Australia’s natural wonder is in mortal danger. Bleaching caused by climate change has killed almost a quarter of its coral this year and many scientists believe it could be too late for the rest. Using exclusive photographs and new data, a Guardian special report investigates how the reef has been devastated – and what can be done to save it

It was the smell that really got to diver Richard Vevers. The smell of death on the reef.

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To save the Great Barrier Reef 'we need to start now, right now' – video

The Guardian - Tue, 2016-06-07 09:42

Jon Brodie from James Cook University says to give the Great Barrier Reef even a fighting chance to survive, Australia needs to spend $1bn a year for the next 10 years to improve water quality. If we don’t do that now, he says, we might need to just give up on the reef. ‘Climate change is happening much more quickly and much more severely than most scientists predicted’

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Coral bleaching 'has changed the Great Barrier Reef forever' – video

The Guardian - Tue, 2016-06-07 09:37

Terry Hughes from James Cook University in Queensland leads a taskforce measuring the condition of the Great Barrier Reef amid a global coral bleaching event that is ‘off the scale’. ‘The kind of bleaching we’re seeing now is an entirely modern phenomenon,’ he says. ‘We’re now in a very precarious position, where every El Niño that comes along, every five or six years, can potentially bleach the entire Great Barrier Reef’

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Great Barrier Reef: diving in the stench of millions of rotting animals – video

The Guardian - Tue, 2016-06-07 09:36

Richard Vevers from the Ocean Agency had never experienced anything like the devastation he witnessed in May diving around the dead and dying coral reefs off Lizard Island on the Great Barrier Reef. When his team emerged from the water, he says, ‘We realised we just stank – we stank of the smell of rotting animals.’ The reefs around the island have been ravaged by coral bleaching caused by climate change

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