Why scientists need your help to spot blue whales off Australia’s east coast


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Vanessa Pirotta, Macquarie UniversityBlue whales, the largest animals to ever live, are surprisingly elusive.

They’re bigger than the biggest dinosaur ever was, capable of growing over 30 metres long and can weigh over 100 tonnes — almost as long as a 737 plane and as heavy as 40 elephants. They also have one of the loudest voices, and can talk to each other hundreds of kilometres across the sea.

Why, then, are they so difficult to find in some parts off Australia?

My new research paper recorded only six verified sightings of the pygmy blue whale off Sydney in the last 18 years. Two of these occurred just last year. This blue whale subspecies is known to mostly occur along Australia’s west coast.

Rare sightings like these are important because pygmy blue whales are a “data deficient” animal. Every opportunity we have to learn about them is crucial to help us better protect them.

Blue whales down under

Don’t let its name fool you, the pygmy blue whale can still grow shockingly large, up to 24 metres in length. It’s one of two blue whale subspecies that occur in Australian waters – the other being the Antarctic blue whale, the biggest whale of them all at around 33 metres long.

A blue whale lunging for krill.

Unfortunately, historical whaling hunted blue whales to near extinction in the Southern Ocean. The Antarctic blue whale was depleted to only a few hundred individuals and, while they’re slowly bouncing back, they’re still listed as critically endangered by the International Union for the Conservation of Nature (IUCN).

In contrast, we know little about pre- and post-whaling numbers for pygmy blue whales. Their listing as a data deficient species by the IUCN means we don’t have a full understanding of their population status.

Blue whales can grow to around 30 metres, almost the same length as a 737 plane.
Vanessa Pirotta, Author provided

One reason may be because blue whales are logistically challenging to study. For example, blue whales don’t just hang around in one area all the time. They’re capable of swimming thousands of kilometres for food and to breed.

They can also hold their breath for up to 90 minutes underwater, which can make them hard to spot unless they’re near the surface. To see them, people need to be in the right place at the right time.

This may require scientists to be on dedicated research vessels or in a plane to spot them, which can be expensive and weather-dependent.




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This also makes learning about them much harder compared to other, more accessible species, such as coastal bottlenose dolphins.

To learn more about pygmy blue whales in Australia, marine scientists have developed a variety of techniques, including listening to whales talking, taking skin samples and satellite tagging.

While this work is useful, it has focused mainly in areas where pygmy blue whales are known to occur, such as southern and western Australian waters.

Pygmy blue whales are known to feed in the Perth Canyon, Western Australia, and between the Great Australian Bight and Bass Strait during summer. They most likely breed in the Indian and western Pacific Oceans during winter.

But we don’t know much about pygmy blue whale presence in other parts of Australian waters, such as the east coast.

Two bottle nose dolphins
Bottlenose dolphins are more commonly seen.
Shutterstock

How can we conserve a species we know very little about?

Well, it can be tricky. The more information we know, the better we’re placed to assess their conservation needs. But focusing our efforts on species we know nothing about may require a conservative approach until we learn more.

Some would argue it’s better to protect a species we know needs our conservation dollar before spending precious resources on something uncertain.




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Curious kids: do whales fart and sneeze?


Fortunately, Australia has some of the world’s best protection policies for marine mammals, including whales. This means a precautionary approach is already in place to protect these creatures.

Since blue whales are listed as a threatened species, they’re protected under Australia’s primary environment law, the Environmental Protection and Biodiversity Conservation (EPBC) Act.

And on an international level, Australia is a signatory to the International Whaling Commission (the global body for whale conservation) and the Convention on International Trade of Endangered Species (which ensures wildlife trade doesn’t threaten endangered species).

Two blue whales near a boat
Citizen science sightings help contribute to our understanding of blue whale distributions in Australian waters.
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To help uphold this international and national protection, scientists must continue to learn more about data-deficient animals like the pygmy blue whale to help safeguard against known and future threats.

This includes collisions with ships, overfishing, entanglement with fishing gear, increased human activity in the ocean, and climate change, which may affect when and where whales occur.

We need extra eyes

There are more than 14,600 animal species listed as data deficient by the IUCN.

Some, like the pygmy blue whale, are poorly studied. One reason is because they’re cryptic or boat shy, such as the Australian snubfin dolphin.

Or, they might be tricky to see, such as the false killer whale, whose sightings remain irregular in Australian coastal waters. Opportunities to learn more about them occur when they become stranded.

A false killer whale pokes its head out of the water
False killer whales are another data-deficient marine animal.
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So while citizen science sightings of pygmy blue whales may be rare off the Australian east coast, they do help contribute to our understanding of their distribution in Australian waters.

The two sightings of pygmy blue whales off Maroubra, Sydney, last year were within two months of each other. This was thanks to drones (flown under state rules).




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This prompted my research review of blue whale sightings off Sydney, which found citizen scientists made similar sightings in 2002 – the first official sighting from land off Sydney — and between 2012-14.

We don’t know exactly what type of pygmy blue whales these are (three distinct groups are recognised: the Indo-Australian, New Zealand and Madagascar groups). However, whale calls detected along Australia’s east coast in previous years suggest they’re most likely New Zealand pygmy blue whales, and they could have been heading to breeding waters north of Tonga.

So, the next time you are by the sea, keep a look out and tell a scientist via social media if you see something interesting. You just never know when the world’s biggest, or shiest, animal may turn up out of the blue.




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The Conversation


Vanessa Pirotta, Wildlife scientist, Macquarie University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Climate explained: how the IPCC reaches scientific consensus on climate change


Fabrice Coffrini/AFP via Getty Images

Rebecca Harris, University of Tasmania


CC BY-ND

Climate Explained is a collaboration between The Conversation, Stuff and the New Zealand Science Media Centre to answer your questions about climate change.

If you have a question you’d like an expert to answer, please send it to climate.change@stuff.co.nz


When we say there’s a scientific consensus that human-produced greenhouse gases are causing climate change, what does that mean? What is the Intergovernmental Panel on Climate Change and what do they do?

The Intergovernmental Panel on Climate Change (IPCC) provides the world’s most authoritative scientific assessments on climate change. It provides policymakers with regular assessments of the scientific basis of climate change, its impacts and risks, and options for cutting emissions and adapting to impacts we can no longer avoid.

The IPCC has already released five assessment reports and is currently completing its Sixth Assessment (AR6), with the release of the first part of the report, on the physical science of climate change, expected on August 9.

Each assessment cycle brings together scientists from around the world and many disciplines. The current cycle involves 721 scientists from 90 countries, in three working groups covering the physical science basis (WGI), impacts, adaptation and vulnerability (WGII) and mitigation of climate change (WGIII).

A group photo showing the diversity of people contributing to the Intergovernmental Panel on Climate Change
People contributing to IPCC reports come from 90 countries and different backgrounds. This image shows the Working Group II team.
Author provided

In each assessment round, the IPCC identifies where the scientific community agrees, where there are differences of opinion and where further research is needed.

IPCC reports are timed to inform international policy developments such as the UN Framework Convention on Climate Change (UNFCCC) (First Assessment, 1990), the Kyoto Protocol (Second Assessment, 1995) and the Paris Agreement (Fifth Assessment, 2013-2014). The first AR6 report (WGI) will be released in August this year, and its approval meeting is set to take place virtually, for the first time in the IPCC’s 30-year history.

This will be followed by WGII and WGIII reports in February and March 2022, and the Synthesis Report in September 2022 — in time for the first UNFCCC Global Stocktake when countries will review progress towards the goal of the Paris Agreement to keep warming below 2℃.

During the AR6 cycle, the IPCC also published three special reports:

Graph of curent warming across the globe.
The IPCC’s special report on global warming at 1.5 showed present-day warming across the globe.
IPCC, CC BY-ND

How the IPCC reaches consensus

IPCC authors come from academia, industry, government and non-governmental organisations. All authors go through a rigorous selection process — they must be leading experts in their fields, with a strong publishing record and international reputation.

Author teams usually meet in person four times throughout the writing cycle. This is essential to enable (sometimes heated) discussion and exchange across cultures to build a truly global perspective. During the AR6 assessment cycle, lead author meetings (LAMs) for Working Group 1 were not disrupted by COVID-19, but the final WGII and WGIII meetings were held remotely, bringing challenges of different time zones, patchy internet access and more difficult communication.




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The IPCC’s reports go through an extensive peer review process. Each chapter undergoes two rounds of scientific review and revision, first by expert reviewers and then by government representatives and experts.

This review process is among the most exhaustive for any scientific document — AR6 WGI alone generated 74,849 review comments from hundreds of reviewers, representing a range of disciplines and scientific perspectives. For comparison, a paper published in a peer-reviewed journal is reviewed by only two or three experts.

The role of governments

The term intergovernmental reflects the fact that IPCC reports are created on behalf of the 193 governments in the United Nations. The processes around the review and the agreement of the wording of the Summary for Policymakers (SPM) make it difficult for governments to dismiss a report they have helped shape and approved during political negotiations.

Importantly, the involvement of governments happens at the review stage, so they are not able to dictate what goes into the reports. But they participate in the line-by-line review and revision of the SPM at a plenary session where every piece of text must be agreed on, word for word.

Acceptance in this context means that governments agree the documents are a comprehensive and balanced scientific review of the subject matter, not whether they like the content.




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The role of government delegates in the plenary is to ensure their respective governments are satisfied with the assessment, and that the assessment is policy relevant without being policy prescriptive. Government representatives can try to influence the SPM wording to support their negotiating positions, but the other government representatives and experts in the session ensure the language adheres to the evidence.

Climate deniers claim IPCC reports are politically motivated and one-sided. But given the many stages at which experts from across the political and scientific spectrum are involved, this is difficult to defend. Authors are required to record all scientifically or technically valid perspectives, even if they cannot be reconciled with a consensus view, to represent each aspect of the scientific debate.

The role of the IPCC is pivotal in bringing the international science community together to assess the science, weighing up whether it is good science and should be considered as part of the body of evidence.The Conversation

Rebecca Harris, Senior Lecturer in Climatology, Director, Climate Futures Program, University of Tasmania

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Breakthrough allows scientists to determine the age of endangered native fish using DNA


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Benjamin Mayne, CSIROIdentifying the age of animals is fundamental to wildlife management. It helps scientists know if a species is at risk of extinction and the rate at which it reproduces, as well as determining what level of fishing is sustainable.

Determining the age of fish has been difficult in the past — primarily involving extracting the inner ear bone, also known as the “otolith”. Layers of growth in the otolith are counted like rings on a tree to reveal an individual’s age. Unless a dead specimen is available, this method requires killing a fish, making it unsuitable for use on endangered populations.

However a non-lethal DNA test developed by the CSIRO enables researchers to determine fish age for three iconic and threatened Australian freshwater species: the Australian lungfish, the Murray cod and the Mary River cod. We outline the technological breakthrough in our research just published.

Our fast, accurate and cost-effective test can be adapted for other fish species. We now hope to share this method to improve the protection of wild fish populations and help promote sustainable fisheries around the world.

gloved hands cut open fish with sciessors
Traditionally, age could only be determined on a dead fish. The new method is non-lethal.
Shutterstock

Iconic species at risk

Human activity has led to the population declines of the three Australian fish species at the centre of our research.

The threatened Australian lungfish is found in rivers and lakes in southeast Queensland. It’s often referred to as a “living fossil” because its extraordinary evolutionary history stretches back more than 100 million years, before all land animals including dinosaurs.

Man-made barriers in rivers reduce the movement of water, which lowers lungfish breeding rates.

Older lungfish do not have hard otolith structures, which makes determining their age difficult. Bomb radiocarbon, which analyses carbon levels in organic matter, has been used to age Australian lungfish, but this method is too expensive to be widely used.

Australian lungfish
In the past, determining the age of Australian lungfish has been challenging.

The threatened Murray cod is Australia’s largest freshwater fish. The Mary River cod is one of Australia’s most endangered fish, found in less than 30% of its former range in Queensland’s Mary River.

Habitat destruction and overfishing are major threats to Murray cod and Mary River cod populations.

Otoliths can be used to determine age for both these cod species, however this has only been done on a population-wide scale for the more prevalent Murray cod.




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Australia’s smallest fish among 22 at risk of extinction within two decades


Mary River cod
CSIRO estimated the age of Mary River cod.

Our DNA breakthrough

When cells divide to make new cells, DNA is replicated. This can lead to DNA methylation, which involves the addition or the loss of a “methyl group” molecule at places along the DNA strand.

Research has found the level of DNA methylation is a reliable predictor of age, particularly in mammals, including humans.

To develop our test, we first worked with zebrafish. This species is useful when studying fish biology because it has a short lifespan and high reproductive rates. We took zebrafish whose ages were known, then removed a tiny clip of their fin. We then examined DNA methylation levels in the fin sample to identify the fish’s age.

Following this successful step, we transferred the method to Australian lungfish, Murray cod and Mary River cod. Again, we used fish of known ages, as well as bomb radiocarbon dating of scales and ages determined from otoliths.

We found despite the zebrafish and the study fish species being separated by millions of years of evolution, our method worked in all four species. This suggests the test can be used to predict age in many other fish species.




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DNA strand
The test uses co-called DNA methylation to estimate age.
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A conservation management boom?

In the same way human population demographers use census data to understand and model human populations, we now have the tools to do this with animals.

We are looking to expand this DNA-based method to determine the age of the endangered eastern freshwater cod and trout cod. We will also continue to test the method across other species including reptiles and crustaceans.

This work is part of CSIRO’s ongoing efforts to use DNA to measure and monitor the environment. This includes estimating the lifespan of vertebrate species such as long-lived fish and surveying biodiversity in seawater using DNA extracted from the environment.

We envisage that in the not too distant future, these methods may be used by other researchers to better understand and manage wild animal populations.




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The Conversation


Benjamin Mayne, Molecular biologist and bioinformatician, CSIRO

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Is Malcolm Turnbull the only Liberal who understands economics and climate science – or the only one who’ll talk about it?


Darren England/AAP

Richard Denniss, Crawford School of Public Policy, Australian National UniversityYesterday, former Liberal prime minister Malcolm Turnbull was unceremoniously dumped as chair of the New South Wales government’s climate advisory board, just a week after being offered the role. His crime? He questioned the wisdom of building new coal mines when the existing ones are already floundering.

No-one would suggest building new hotels in Cairns to help that city’s struggling tourism industry. But among modern Liberals it’s patently heresy to ask how rushing to green light 11 proposed coal mines in the Hunter Valley helps the struggling coal industry.

Coal mines in the Hunter are already operating well below capacity and have been laying off workers in the face of declining world demand for coal, plummeting renewable energy prices and trade sanctions imposed by China. The problem isn’t a shortage of supply, but an abundance.

The simple truth is building new coal mines will simply make matters worse, especially for workers in existing coal mines that have already been mothballed or had their output scaled back.

coal mine in the Hunter Valley
Turnbull has called for a moratorium on new coal mines in the Hunter Valley, such as the one pictured above.
Dean Lewins/AAP

It gets worse. Once an enormous, dusty, noisy open cut coal mine is approved, the agriculture, wine, tourism and horse breeding industries – all major employers in the Hunter Valley – are reluctant to invest nearby. While building new coal mines hurts workers in existing coal mines, the mere act of approving new coal mines harms investment in job creation in the industries that offer the Hunter a smooth transition from coal.

The NSW planning department doesn’t have a plan for how many new coal mines are needed to meet world demand. Nor does it have a plan for how much expansion of rail and port infrastructure is required to meet the output of all the new mines being proposed.




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That’s why my colleagues and I recently called for a moratorium on new coal mines in the Hunter until such plans were made explicit. Just as you wouldn’t approve 1,000 new homes in a town where the sewerage system was already at capacity, it makes no sense to approve 11 new coal mines in a region that couldn’t export that much coal if it tried.

But if there’s one thing that defines the debate about coal in Australia, its that it makes no sense.

Just as it made no sense for then-treasurer Scott Morrison to wave a lump of coal around in parliament in 2017, it makes no sense for right-wing commentators to pretend approving new mines will help create jobs in coal mining. And it makes no sense for the National Party to ignore the pleas of farmers to protect their land from the damage coal mines do.

Scott Morrison with a lump of coal to Question Time in 2017.
Scott Morrison took a lump of coal to Question Time in 2017.
Lukas Coch/AAP

On the surface, Turnbull’s support for a pause on approving new mines while a plan is developed is old-fashioned centrism. It protects existing coal workers from new, highly automated mines, it protects farmers and it should make those concerned with climate change at least a bit happy. Win. Win. Win.

But there’s no room for a sensible centre in the Australian coal debate. And when someone even suggests the industry might not be set to grow, its army of loyal parliamentary and media supporters swing into action.

Labor’s Joel Fitzgibbon said Turnbull “wants to make the Upper Hunter a coal-mine-free zone”. The Nationals’ Matt Canavan suggested stopping coal exports was “an inhumane policy to keep people in poverty”. The head of the NSW Minerals Council suggested 12,000 jobs were at risk.

But of course, the opposite is true. Turnbull’s proposal to protect existing coal workers from competition from new mines would save jobs, not threaten them. He didn’t suggest coal mines be shut down tomorrow, or even early. And, given existing coal mines are running so far below capacity, his call has no potential to impact coal exports.




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Coal workers
Opening new coal mines won’t help save the jobs of existing coal workers.
Dan Himbrechts/AAP

Predictably, the Murdoch press ran a relentlessly misleading campaign in support of the coal industry and in opposition to their least favourite Liberal PM. But surprisingly, the NSW government rolled over in record time.

While the government might think appeasing the coal industry will play well among some older regional voters, they must know such kowtowing is a gift to independents such as Zali Steggall, and a fundamental threat to inner-city Liberals such as Dave Sharma, Jason Falinski and Trent Zimmerman.

The decision to dump Turnbull might have bought NSW Premier Gladys Berejiklian some respite from attacks from the Daily Telegraph. But such denial of economics and climate science will provide no respite for existing coal workers in shuttered coal mines or the agriculture and tourism industry that is looking to expand.

No doubt the National Party are pleased with their latest scalp. But it must be remembered this is the party that last year wanted to wage a war against koalas on behalf of property developers. Such political instincts might help the Nationals fend off the threat from One Nation in regional areas but it does nothing to retain votes in leafy Liberal strongholds that deliver most Liberal seats.




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The Conversation


Richard Denniss, Adjunct Professor, Crawford School of Public Policy, Australian National University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

‘It is not easy’: how science and courage saved the stunning Australian Alps



National Library of Australia

Philip Gibbons, Australian National University

Most people probably associate the Australian Alps with skiing and snow. Others might think of the Man from Snowy River legend or the engineering feats of the Snowy Hydro-Electric Scheme.

But few people know the region’s history of exploitation and overuse, nor the courage of those who fought to save this precious wilderness area. A new book, Kosciuszko: A Great National Park, tells that important story. The result, by authors Deirdre Slattery and Graeme L. Worboys, is a positive yet cautionary tale.

Today, the park is largely protected – yet threats such as ski tourism, feral horses and the Snowy 2.0 scheme still loom. And climate change has left the region highly vulnerable, as shown by declining snow depths and a massive bushfire that tore through the Snowy Mountains last summer.

The book shows how Kosciuszko National Park is the product of robust science and hard-fought battles by dedicated individuals – battles that continue to this day.

A ranger-guided tour leaving for the Kosciuszko summit in 1964.
A ranger-guided tour leaving for the Kosciuszko summit in 1964.
Gare collection in Kosciuszko: A Great National Park

A long history of occupation

The Australian Alps in southeast New South Wales is the traditional home of three Aboriginal groups: the Ngarigo, Walgalu and Djilamatang people. It is home to Australia’s highest peak, Mount Kosciuszko.

The book describes how squatters with cattle occupied the region from the 1820s. By 1840, the Snowy region had been stocked with 200,000 sheep, 75,000 cattle and 3,000 horses which grazed in the mountains each summer.




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The discovery of gold in 1860 brought another 10,000 people to the Snowy Mountains. By the turn of the 20th century, the mountains were also a playground for recreation. Hotel Kosciusko, with 93 bedrooms, a ballroom, museum, skating rink and tennis courts, catered for an upmarket clientele.

In 1949 the mountains became the site for the Snowy Mountains Hydro-Electric Scheme: 16 dams, 80 kilometres of aqueducts and more than 140 kilometres of tunnels.

By then, the signs of overuse were evident. Soils were eroding, streams became silted and unique alpine flora was diminishing.

Cattle grazing at Club Lake believed to be during the Federation Drought (1897-1903).
Cattle grazing at Club Lake believed to be during the Federation Drought (1897-1903).
Kerry Studio/Costin collection in Kosciuszko: A Great National Park.

The long conservation fight

Tannat William Edgeworth David, a professor at the University of Sydney, was one of the first to document the unique values of the Snowy Mountains and call for their protection.

In the 1800s, the notion that an ice age once gripped Australia was considered preposterous. The book tells how David and colleagues put the matter “absolutely beyond dispute” when they mapped, on Kosciuszko’s main range, the undeniable signature left by glaciers.

In the early 1900s, David urged that the alpine area be preserved:

[I]t would be wise policy, in the interest of people and of science, to reserve from occupation and even from the depasturing of stock, all the highest points of our alpine plateau, so that this floral wonderland may be preserved intact for posterity…

It took almost 50 years before this advice was heeded. Kosciuszko State Park — later Kosciuszko National Park – was proclaimed in 1944. A decade of further scientific research led to the end of summer grazing leases above 1,350 metres in 1958.

One of the first park managers was Neville Gare. As the book notes, Gare quickly learned that feelings over management of the mountains ran deep. Soon after rangers started impounding stock found illegally in the park, an effigy of a park ranger swinging from a hangman’s noose was installed on the veranda of the Jindabyne Hotel.




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Fire almost wiped out rare species in the Australian Alps. Feral horses are finishing the job


In 1950, Gare resisted a plan by head of the Ski Tourers Association, Charles Anton, to build a network of ski lodges. The book recounts how the tensions culminated at a public function when Anton snipped Gare’s tie in half to “indicate his indifference to Gare’s authority”. Some lodges were later built.

In his unpublished memoir, Gare wrote “it is not easy to conserve something and use it too”. In future years, this observation would prove all too true.

Stock illegally moved into the park after grazing leases ended in 1958.
Stock illegally moved into the park after grazing leases ended in 1958.
Alec Costin in Kosciuszko: A Great National Park

Ongoing battles

Gare and the Kosciusko State Park Trust developed the first formal plan of management for the park in 1965. The park was divided into zones for different uses: wilderness, conservation of exceptional natural and historic features, development, hydro-electricity and tourism.

This zoning was radical thinking at the time but has since been widely adopted in park management across Australia.

The plan of management for Kosciuszko National Park has been frequently amended to accommodate more tourism facilities, and the threat of further development is ever-present. As the authors note, further pressure is also coming via Snowy 2.0, a A$5 billion proposal to expand the current hydroelectric scheme.

Climate change is also a threat. Rising temperatures have triggered a 15% decline in the annual maximum snow depth, relative to the 1961-90 average.

Skiers at Perisher Valley
Climate change is reducing the snow depth in the region.
Perisher/AAP

Climate change is also making the threat of bushfires worse. In January, the massive Adaminaby Complex fire burned through more than 93,000 hectares in the Snowy region, affecting swathes of bush. It also devastated populations of several threatened species, including the corroboree frog and the stocky galaxias fish.

And the lethal chytrid fungus, introduced to Australia, has pushed the park’s southern corroboree frog to the brink of extinction.




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In 2018, the NSW government declared feral horses in the park a protected species. The population has quickly grown to about 19,000, representing a considerable threat to several species.

The book reminds us that today, as throughout history, Kosciuszko National Park needs protecting. And key to that are courageous, committed individuals – and robust science.The Conversation

A scenic view of the Snowy Mountains
The Snowy Mountains are protected, but threats remain.
Schopier/Wikimedia

Philip Gibbons, Professor, Australian National University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

How a scientific spat over how to name species turned into a big plus for nature



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Stephen Garnett, Charles Darwin University; Les Christidis, Southern Cross University; Richard L. Pyle, University of Hawaii, and Scott Thomson, Universidade de São Paulo

Taxonomy, or the naming of species, is the foundation of modern biology. It might sound like a fairly straightforward exercise, but in fact it’s complicated and often controversial.

Why? Because there’s no one agreed list of all the world’s species. Competing lists exist for organisms such as mammals and birds, while other less well-known groups have none. And there are more than 30 definitions of what constitutes a species. This can make life difficult for biodiversity researchers and those working in areas such as conservation, biosecurity and regulation of the wildlife trade.

In the past few years, a public debate erupted among global taxonomists, including those who authored and contributed to this article, about whether the rules of taxonomy should be changed. Strongly worded ripostes were exchanged. A comparison to Stalin was floated.

But eventually, we all came together to resolve the dispute amicably. In a paper published this month, we proposed a new set of principles to guide what one day, we hope, will be a single authoritative list of the world’s species. This would help manage and conserve them for future generations.

In the process, we’ve shown how a scientific stoush can be overcome when those involved try to find common ground.

Baby crocodile emerging from egg.
Scientists worked out a few differences over how to name species.
Laurent Gillieron/EPA

How it all began

In May 2017 two of the authors, Stephen Garnett and Les Christidis, published an article in Nature. They argued taxonomy needed rules around what should be called a species, because currently there are none. They wrote:

for a discipline aiming to impose order on the natural world, taxonomy (the classification of complex organisms) is remarkably anarchic […] There is reasonable agreement among taxonomists that a species should represent a distinct evolutionary lineage. But there is none about how a lineage should be defined.

‘Species’ are often created or dismissed arbitrarily, according to the individual taxonomist’s adherence to one of at least 30 definitions. Crucially, there is no global oversight of taxonomic decisions — researchers can ‘split or lump’ species with no consideration of the consequences.

Garnett and Christidis proposed that any changes to the taxonomy of complex organisms be overseen by the highest body in the global governance of biology, the International Union of Biological Sciences (IUBS), which would “restrict […] freedom of taxonomic action.”




Read more:
Taxonomy, the science of naming things, is under threat


An animated response

Garnett and Christidis’ article raised hackles in some corners of the taxonomy world – including coauthors of this article.

These critics rejected the description of taxonomy as “anarchic”. In fact, they argued there are detailed rules around the naming of species administered by groups such as the International Commission on Zoological Nomenclature and the International Code of Nomenclature for algae, fungi, and plants. For 125 years, the codes have been almost universally adopted by scientists.

So in March 2018, 183 researchers – led by Scott Thomson and Richard Pyle – wrote an animated response to the Nature article, published in PLoS Biology.

They wrote that Garnett and Christidis’ IUBS proposal was “flawed in terms of scientific integrity […] but is also untenable in practice”. They argued:

Through taxonomic research, our understanding of biodiversity and classifications of living organisms will continue to progress. Any system that restricts such progress runs counter to basic scientific principles, which rely on peer review and subsequent acceptance or rejection by the community, rather than third-party regulation.

In a separate paper, another group of taxonomists accused Garnett and Christidis of trying to suppress freedom of scientific thought, likening them to Stalin’s science advisor Trofim Lysenko.

Sea sponge under a microscope
Taxonomy can influence how conservation funding is allocated.
Queensland Museum

Finding common ground

This might have been the end of it. But the editor at PLoS Biology, Roli Roberts, wanted to turn consternation into constructive debate, and invited a response from Garnett and Christidis. In the to and fro of articles, we all found common ground.

We recognised the powerful need for a global list of species – representing a consensus view of the world’s taxonomists at a particular time.




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Summer bushfires: how are the plant and animal survivors 6 months on? We mapped their recovery


Such lists do exist. The Catalogue of Life, for example, has done a remarkable job in assembling lists of almost all the world’s species. But there are no rules on how to choose between competing lists of validly named species. What was needed, we agreed, was principles governing what can be included on lists.

As it stands now, anyone can name a species, or decide which to recognise as valid and which not. This creates chaos. It means international agreements on biodiversity conservation, such as the Convention on International Trade in Endangered Species (CITES) and the Convention on the Conservation of Migratory Species of Wild Animals (CMS), take different taxonomic approaches to species they aim to protect.

We decided to work together. With funding from the IUBS, we held a workshop in February this year at Charles Darwin University to determine principles for devising a single, agreed global list of species.

Pengiuns embracing each other.
The sparring scientists came together to develop agreed principles.
Shutterstock

Participants came from around the world. They included taxonomists, science governance experts, science philosophers, administrators of the nomenclatural (naming) codes, and taxonomic users such as the creators of national species lists.

The result is a draft set of ten principles that to us, represent the ideals of global science governance. They include that:

  • the species list be based on science and free from “non-taxonomic” interference
  • all decisions about composition of the list be transparent
  • governance of the list aim for community support and use
  • the listing process encompasses global diversity while accommodating local knowledge.

The principles will now be discussed at international workshops of taxonomists and the users of taxonomy. We’ve also formed a working group to discuss how a global list might come together and the type of institution needed to look after it.

We hope by 2030, a scientific debate that began with claims of anarchy might lead to a clear governance system – and finally, the world’s first endorsed global list of species.


The following people provided editorial comment for this article: Aaron M Lien, Frank Zachos, John Buckeridge, Kevin Thiele, Svetlana Nikolaeva, Zhi-Qiang Zhang, Donald Hobern, Olaf Banki, Peter Paul van Dijk, Saroj Kanta Barik and Stijn Conix.

The Conversation

Stephen Garnett, Professor of Conservation and Sustainable Livelihoods, Charles Darwin University; Les Christidis, Professor, Southern Cross University; Richard L. Pyle, Associate lecturer, University of Hawaii, and Scott Thomson, Research associate, Universidade de São Paulo

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Australia listened to the science on coronavirus. Imagine if we did the same for coal mining



Dan Peled/AAP

Matthew Currell, RMIT University; Adrian Werner, Flinders University; Chris McGrath, The University of Queensland, and Dylan Irvine, Flinders University

Australia’s relative success in stopping the spread of COVID-19 is largely due governments taking expert advice on a complex problem. Unfortunately, the same cannot be said of decisions on projects that threaten the environment – most notably, Adani’s Carmichael coal mine.

Our research published today in Nature Sustainability documents how state and federal governments repeatedly ignored independent scientific advice when assessing and approving the Adani mine’s groundwater plans.

We interrogated scientific evidence available to governments and Adani over almost a decade. Our analysis shows governments failed to compel Adani to fully investigate the environmental risks posed by its water plans, despite concerns raised by scientists.

There is also evidence the government approval decisions were influenced by the political climate and pressure exerted by members of government.

Our findings come as the Morrison government conducts a ten-yearly review of the Environmental Protection and Biodiversity Conservation (EPBC) Act. It is critical these laws – Australia’s most important environmental legislation – are reformed to put rigorous, independent science at the core.

Advice ignored

In mid-2019, the federal and Queensland governments approved groundwater management plans for Adani’s Carmichael coal mine. It granted the company unlimited access to groundwater in central Queensland’s Galilee Basin.

We and other experts warned the mine threatens to damage aquifers, rivers and ecosystems – in particular, the Doongmabulla Springs Complex. This system contains more than 150 wetlands which support rare plant communities found nowhere else on earth.

The springs are of major cultural significance to the Wangan and Jagalingou people.

We analysed the full suite of evidence on the groundwater plans from agencies and scientists with expertise in hydro-geology. The evidence, provided to state and federal environment ministers, spanned almost a decade and included at least six independent scientific reviews.

The evidence highlighted major shortcomings, and gaps in knowledge and data.




Read more:
Unpacking the flaws in Adani’s water management plan


For example in 2013, the federal government’s Independent Expert Scientific Committee on Coal Seam Gas and Large Coal Mining Development (IESC) said key geological characteristics in Adani’s groundwater model were not consistent with available field data.

Expert evidence from court-appointed hydro-geology witnesses in the Land Court of Queensland reiterated this concern and raised new questions over whether the source aquifer for the Doongmabulla Springs had been incorrectly identified.

Subsequent joint reviews by CSIRO and Geoscience Australia in February and June 2019 found Adani had failed to conclusively resolve these issues. The agencies also identified further flaws in Adani’s modelling, including interaction between groundwater and the Carmichael River that was again not consistent with field evidence.

The CSIRO and Geoscience Australia concluded the model was “not suitable to ensure the outcomes sought by the EPBC Act conditions are met”.

Moses 3 Lagoon in the Doongmabulla Springs Complex. Source: Land Services of Coast and Country Inc (2014)

Governments under pressure

The federal government received the reviews from CSIRO and Geoscience Australia in February 2019. It did not publicly release them until then-environment minister Melissa Price announced approval of the groundwater plans on April 8. This was effectively the final federal approval the mine needed to proceed.

Media reports at the time suggested Price had been pressured by members of her government to issue approval before the election. What’s more, her department reportedly pushed the CSIRO to endorse Adani’s plans in just hours, and in the absence of critical information.

Within 48 hours of Adani’s approval being announced, the government called a federal election.




Read more:
Morrison government approves next step towards Adani coal mine


The Coalition was returned to power at the election. Federal Labor suffered heavy losses in regional Queensland – a result many claimed was due to their lukewarm support for the Adani mine.

The Queensland Labor government was also required to sign off on the groundwater plans. Following the federal election result, Premier Annastacia Palaszczuk directed that the assessment be completed quickly. The state approved the plans within four weeks.

This was despite being provided a scientific analysis by authors of this article and others, outlining key remaining scientific deficiencies in the groundwater plans.

Once-in-a-decade chance

Our analysis exposes flaws in how evidence informs major government decisions. It also shows why reform of the Environmental Protection and Biodiversity Conservation Act is so urgent.

The laws are currently under review. Many reputable organisations and scholars have proposed ways the legislation can better protect the environment, increase its independence from government and put science at the core.

Independent scientific committees, such as the federal IESC, are commissioned by governments to advise on mining proposals. We suggest such committees be granted greater powers to request specific data and studies from mining companies to address knowledge gaps before advice is issued.

Alternatively – or in addition – a new independent national commission should be established to oversee environmental impact assessments conducted by mining and other development proponents.

This commission should be empowered to interrogate and resolve key scientific uncertainties, free from political interference. Its recommendations to government should take into account a wide range of expert advice and public feedback.

Doongmabulla Springs, a desert oasis scientists say is at risk from the Adani mine.
Flickr

This would not only improve the evidence base for decisions, but may also speed up assessments – ensuring more effective resolution of uncertainties that often lead to protracted conflict and debate about a mine’s impacts.

Such reform is urgently needed. Australia is suffering unprecedented water stress, environmental harm and declining trust in government.

Australian governments listened to the science when it needed to flatten the curve of COVID-19. The same approach is needed if we’re to preserve the places we love and the ecosystems we depend on.




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Our nature laws are being overhauled. Here are 7 things we must fix


An Adani spokesperson provided the following response to the claims raised by the authors:

Adani’s Groundwater Dependent Ecosystems Management Plan (GDEMP) was finalised and approved by both the Australian and Queensland governments almost 12 months ago, bringing to an end more than eight years of heavily scrutinised planning and approvals processes.

The approvals were confirmation that the GDEMP complies with all regulatory conditions, following an almost two-year process of rigorous scientific inquiry, review and approvals. This included relevant independent reviews by Australia’s pre-eminent scientific organisations CSIRO and Geoscience Australia.

There are more than 270 conditions within the mine approvals to protect the natural environment and more than 100 of those relate to groundwater.

We’re now getting on with construction of the Carmichael Mine and Rail project, having awarded more than $750 million in contracts to the benefit of regional Queenslanders.

We remain on track to create more than 1,500 direct jobs during the construction and ramp up of our project and some further 6,750 indirect jobs. At a time when our country is facing some of its toughest challenges, we’re determined to deliver on our commitments of jobs and opportunities.The Conversation

Matthew Currell, Associate Professor in Environmental Engineering, School of Engineering, RMIT University; Adrian Werner, Professor of Hydrogeology, Flinders University; Chris McGrath, Associate Professor in Environmental and Planning Regulation and Policy, The University of Queensland, and Dylan Irvine, Senior lecturer in hydrogeology, Flinders University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

The burn legacy: why the science on hazard reduction is contested


Kevin Tolhurst, University of Melbourne

When it comes to reducing the extent of bushfires, scientists disagree on the best way to do it. Hazard-reduction burning (also known as “prescribed burning” or “controlled burning”) is controversial and, depending on the scientific paper, it’s shown to either be effective or not work at all.

Hazard-reduction burning is the process of removing vegetation that would fuel a fire – the “hazard” – through burning, slashing or grazing. It’s one of the ways state governments try to prepare for looming bushfire seasons.




Read more:
There’s no evidence ‘greenies’ block bushfire hazard reduction but here’s a controlled burn idea worth trying


The Climate Council published a fact sheet in January this year titled “Setting the record straight on hazard reduction”. It concluded that, while important, in future “no amount of hazard reduction will protect human lives, animals and properties from catastrophic fires”.

But this is at odds with empirical studies in Victoria and Western Australia, which found otherwise, after taking a wider view on the issue.

So why are there conflicting views?

Hazard-reduction burns don’t help: a 2015 study

For its report, the Climate Council relied heavily on a 2015 study based on fire and weather records from southeastern Australia over a period of 34 years. This is a relatively short time when it comes to ecosystem cycles – the earth’s natural recycling process of resources like water and carbon.

The researchers of this study used a metric called “leverage” to evaluate the effect of hazard-reduction burning on reducing the extent of wildfires. “Leverage” in this context refers to the ratio between the area burnt by wildfires and the area burnt by prescribed burning.

And they concluded hazard-reduction burning has a statistically significant effect on the extent of wildfires, but only in forested areas with distinct annual drought periods.




Read more:
A surprising answer to a hot question: controlled burns often fail to slow a bushfire


The leverage measure implies that prescribed burning only increases the total area burnt, and is therefore ineffective in reducing fire extent.

Like all scientific papers, the conclusions of the 2015 paper are drawn from several assumptions. And while the conclusions are valid for the researchers’ focus, several assumptions don’t work in a land management context. For instance, it’s assumed only the extent of the area burnt is important, rather than the severity.

But the recovery of the plants, animals, nutrients and habitat after low-intensity fire is much quicker than after high-intensity wildfire, according to a long-term Victorian study.

Several other assumptions were also made in the 2015 study, and it is such assumptions that lead to conflicting conclusions with others. While this study is valid within the context in which it was undertaken and includes useful analysis, the conclusions the Climate Council draws from it aren’t supported.

Hazard-reduction burns do help: a 2009 study

A 2009 study looking at 52 years of fire history in southwest Western Australia identified the benefits of hazard-reduction burns. This includes it leading to fewer fires starting and a greater ability to suppress fires in prescribed burnt areas.

A big reason for the different findings is because, unlike the 2009 study, the 2015 study didn’t explicitly consider how past prescribed burns lower the severity of new high-intensity fires when they move in. This helps fire suppression efforts and helps reduce the spread of wildfires.

The 2009 study showed prescribed burning less than about 4% of a million hectares of forested landscape per year wasn’t enough to show trends in reducing wildfires.




Read more:
There’s only one way to make bushfires less powerful: take out the stuff that burns


But in the 2015 study the Climate Council used, only included 2% of prescribed burning in the forested landscape of southeast Australia, so a conclusion that prescribed burning was ineffective could have been expected.

In other words, not enough of the landscape was prescribed burnt to have a measureable effect, so it cannot be concluded that prescribed burning is ineffective at reducing the impact of bushfires from this analysis.

The Climate Council should have taken a broader view of the available scientific studies before drawing its conclusions.

So should we use hazard-reduction burns?

There are many dimensions to the debate about whether to use hazard-reduction burns to mitigate and prepare for wildfires. And not all scientific studies will be equally relevant in addressing particular issues.




Read more:
To fight the catastrophic fires of the future, we need to look beyond prescribed burning


So before we decide whether hazard-reduction burning for land management is a good thing, we need to consider all of the variables. This includes increased ecosystem resilience, mitigation of wildfire number and extent, impact on human health, economic value, social impact, Traditional Owner culture, and more.

The Climate Council’s conclusions are drawn only from the consideration of reduced wildfire extent.

In debating the value or otherwise of prescribed burning, we need to use good scientific evidence, but our decisions must be based on the whole picture, not just a selective part of it.The Conversation

Kevin Tolhurst, Hon. Assoc. Prof., Fire Ecology and Management, University of Melbourne

This article is republished from The Conversation under a Creative Commons license. Read the original article.

The science of drought is complex but the message on climate change is clear



Detecting human fingerprints on complex events like droughts is not straightforward.
AAP Image/Dan Peled

Ben Henley, University of Melbourne; Andrew King, University of Melbourne; Anna Ukkola, Australian National University; Murray Peel, University of Melbourne; Q J Wang, University of Melbourne, and Rory Nathan, University of Melbourne

The issue of whether Australia’s current drought is caused by climate change has been seized on by some media commentators, with debate raging over a remark from eminent scientist Andy Pitman that “there is no link between climate change and drought”. Professor Pitman has since qualified, he meant to say “there is no direct link between climate change and drought”.

A highly politicised debate that tries to corner scientists will not do much to help rural communities struggling with the ongoing dry. But it is still worthwhile understanding the complexity of how climate change relates to drought.




Read more:
Is Australia’s current drought caused by climate change? It’s complicated


So, why the contention?

It may seem like splitting hairs to focus on single words, but the reality is drought is complex, and broad definitive statements are difficult to make. Nevertheless, aspects of drought are linked with climate change. Let us try to give you a taste of the complexity.

First, it’s important to understand that drought is a manifestation of interactions between the atmosphere, ocean, and land. In Australia, the Bureau of Meteorology uses rainfall deficiencies to identify regions that are under drought conditions. Anyone on the land doesn’t need to be reminded, but the current drought is seriously bad. These maps show the patterns of rainfall deficiency over the past 36 and 18 months, highlighting the severity and extent of what we call meteorological drought.

Widespread rainfall deficiencies over the last 36 months (left) and 18 months (right)
Australian Bureau of Meteorology

But along with the main driver – low rainfall – droughts can also be exacerbated by water loss through evaporation. This depends not only on temperature but also humidity, wind speeds, and sunshine. Temperature will clearly continue to rise steadily almost everywhere. For the other factors, the future is not quite as clear.

Water loss also varies according to vegetation cover. Plants respond to higher carbon dioxide levels and drought by closing the tiny holes in their leaves (the stomata) and this can actually reduce water loss in wet environments. However, in water-stressed environments, projected long-term declines in rain may be compounded by plants using more water, further reducing streamflow. Actually, we can glean a lot from studying hydrological drought, which is measured by a period of low flow in rivers.

The point here is droughts are multidimensional, and can affect water supply on a wide range of spatial and temporal scales. A seasonal-scale drought that reduces soil moisture on a farm, and a decade-long drought that depletes reservoirs and groundwater supplies, can each be devastating, but in different ways.

Is climate change affecting Australian droughts?

Climate change may affect drought metrics and types of drought differently, so it can be hard to make general statements about the links between human-induced climate change and all types of drought, in all locations, on all timescales.

Southern Australia, and in particular the southwest, has seen a rapid decline in winter rainfall and runoff that has been linked to climate change. In the southeast there has also been a substantial decline in winter rainfall and total runoff in recent decades. Although the reductions are consistent with climate change projections, the trend so far is harder to distinguish from the year-to-year variability.

There is some evidence to suggest that widespread and prolonged droughts, like the Millennium Drought, are worse than other droughts in past centuries, and may have been exacerbated by climate change.




Read more:
Recent Australian droughts may be the worst in 800 years


But the role of climate change in extended drought periods is difficult to discern from normal variations in weather and climate. This is particularly true in Australia, which has a much more variable climate than many other parts of the world.

What does the future hold?

Climate models project increasing temperature across Australia and a continuing decline in cool-season rainfall over southern Australia over the next century. This will lead to more pressure on water supplies for agriculture, the environment, and cities such as Melbourne at the Paris Agreement’s target of 2℃, relative to the more ambitious target of 1.5℃ of global warming.




Read more:
2℃ of global warming would put pressure on Melbourne’s water supply


Rainfall is projected to become more extreme, with more intense rain events and fewer light rain days. Declining overall rainfall is predicted to reduce river flows in southeastern Australia. While we can expect the largest floods to increase with climate change, smaller floods are decreasing due to drier soils, and it is these smaller floods that top up our water supply systems.

Action needed

We might not know enough about droughts to be certain about exactly how they will behave in the future, but this does not affect the message from the science community on climate change, which remains crystal clear.

Rainfall intensification, sea level rise, ocean acidification, hotter days, and longer and more intense heatwaves all point to the fact that climate change presents a major threat to Australia and the world.

In response to these threats, we need deep and sustained greenhouse gas emissions cuts and proactive adaptation to the inevitable effects of climate change. This includes a focus right now on the practical measures to help our rural communities who continue to feel the pinch of a dry landscape.




Read more:
Why 2℃ of global warming is much worse for Australia than 1.5℃


The Conversation


Ben Henley, Research Fellow in Climate and Water Resources, University of Melbourne; Andrew King, ARC DECRA fellow, University of Melbourne; Anna Ukkola, Research Fellow, Australian National University; Murray Peel, Senior lecturer, University of Melbourne; Q J Wang, Professor, University of Melbourne, and Rory Nathan, Associate Professor Hydrology and Water Resources, University of Melbourne

This article is republished from The Conversation under a Creative Commons license. Read the original article.

40 years ago, scientists predicted climate change. And hey, they were right



It’s been four decades since the first credible, global report on the effect of carbon dioxide on the global climate.
Shutterstock

Neville Nicholls, Monash University

This month the world has been celebrating the 50th anniversary of Neil Armstrong setting foot on the Moon. But this week sees another scientific anniversary, perhaps just as important for the future of civilisation.

Forty years ago, a group of climate scientists sat down at Woods Hole Oceanographic Institution in Massachusetts for the first meeting of the “Ad Hoc Group on Carbon Dioxide and Climate”. It led to the preparation of what became known as the Charney Report – the first comprehensive assessment of global climate change due to carbon dioxide.




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What is a pre-industrial climate and why does it matter?


It doesn’t sound as impressive as landing on the Moon, and there certainly weren’t millions waiting with bated breath for the deliberations of the meeting.

But the Charney Report is an exemplar of good science, and the success of its predictions over the past 40 years has firmly established the science of global warming.

What is this ‘greenhouse gas’ you speak of?

Other scientists, starting in the 19th century, had already demonstrated that carbon dioxide was what we now call a “greenhouse gas”. By the 1950s, scientists were predicting warming of several degrees from the burning of fossil fuels. In 1972 John Sawyer, the head of research at the UK Meteorological Office, wrote a four-page paper published in Nature summarising what was known at the time, and predicting warming of about 0.6℃ by the end of the 20th century.

But these predictions were still controversial in the 1970s. The world had, if anything, cooled since the middle of the 20th century, and there was even some speculation in the media that perhaps we were headed for an ice age.

The meeting at Woods Hole gathered together about 10 distinguished climate scientists, who also sought advice from other scientists from across the world. The group was led by Jule Charney from the Massachusetts Institute of Technology, one of the most respected atmospheric scientists of the 20th century.

The Report lays out clearly what was known about the likely effects of increasing carbon dioxide on the climate, as well as the uncertainties. The main conclusion of the Report was direct:

We estimate the most probable warming for a doubling of CO₂ to be near 3℃ with a probable error of 1.5℃.

In the 40 years since their meeting, the annual average CO₂ concentration in the atmosphere, as measured at Mauna Loa in Hawaii, has increased by about 21%. Over the same period, global average surface temperature has increased by about 0.66℃, almost exactly what could have been expected if a doubling of CO₂ produces about 2.5℃ warming – just a bit below their best estimate. A remarkably prescient prediction.


Author provided/The Conversation, CC BY-ND

Reception of the article

Despite the high regard in which the authors of the Charney Report were held by their scientific peers at the time, the report certainly didn’t lead to immediate changes in behaviour, by the public or politicians.

But over time, as the world has continued to warm as they predicted, the report has become accepted as a major milestone in our understanding of the consequences our actions have for the climate. The current crop of climate scientists revere Charney and his co-authors for their insight and clarity.

Strong science

The report exemplifies how good science works: establish an hypothesis after examining the physics and chemistry, then based on your assessment of the science make strong predictions. Here, “strong predictions” means something that would be unlikely to come true if your hypothesis and science were incorrect.

In this case, their very specific prediction was that warming of between 1.5℃ and 4.5℃ would accompany a doubling of atmospheric CO₂. At the time, global temperatures, in the absence of their hypothesis and science, might have been expected to stay pretty much the same over the ensuing 40 years, cooled a bit, possibly even cooled a lot, or warmed a lot (or a little).

In the absence of global warming science any of these outcomes could have been feasible, so their very specific prediction made for a very stringent test of their science.

The Charney Report’s authors didn’t just uncritically summarise the science. They also acted sceptically, trying to find factors that might invalidate their conclusions. They concluded:

We have tried but have been unable to find any overlooked or underestimated physical effects that could reduce the currently estimated global warmings due to a doubling of atmospheric CO₂ to negligible proportions or to reverse them altogether.

The report, and the successful verification of its prediction, provides a firm scientific basis for the discussion of what we should do about global warming.

Over the ensuing 40 years, as the world warmed pretty much as Charney and his colleagues expected, climate change science improved, with better models that included some of the factors missing from their 1979 deliberations.




Read more:
Climate change or climate crisis? To really engage people, the media should talk about solutions


This subsequent science has, however, only confirmed the conclusions of the Charney Report, although much more detailed predictions of climate change are now possible.The Conversation

Neville Nicholls, Professor emeritus, School of Earth, Atmosphere and Environment, Monash University

This article is republished from The Conversation under a Creative Commons license. Read the original article.