During the 2020 US presidential election campaign, one of the starkest visual differences between Trump and Biden supporters was in the wearing of masks. Most Biden supporters appeared to wear masks, whereas most Trump supporters didn’t.
Even during Trump’s announcement of his nomination of Judge Amy Barrett to the US Supreme Court, very few people in the White House Rose Garden were wearing a mask. Worse still, some of the guests were seen hugging and kissing each other.
As a result, the White House has become a COVID-19 ‘hotspot’ or super-spreader location, with seven attendees at the Justice Amy Barrett nomination announcement testing positive for coronavirus – even President Trump and the First Lady. More people caught the virus at the White House election ‘celebration night’. 130 Secret Service agents have also tested positive.
It is clear that at least some, if not most, of Trump supporters refuse to wear masks on political grounds. They seem to associate mask wearing with what they perceive to be ‘liberal’ pro-science attitudes. It is also possible that some Biden supporters might wear masks as a form of visual political opposition to the Trump supporters. In either case, this is irrational tribal behaviour.
A similar phenomenon may be occurring in the climate change debate. Some beliefs against human causes of climate change may be genuinely (but mistakenly) held on the basis of personal interpretation of the evidence. But at least some of the far-right wing opposition is due to a perception of climate science being some sort of left-wing plot against fossil fuel industries.
The far left is not immune from such irrational tribal behaviour either. At least some of the opposition to GMOs and vaccines seems to be based on ideological opposition to large agribusinesses and the pharmaceutical industry, rather than on evidence-based health concerns.
Another example is where some atheists oppose the idea of free will simply because Christians believe in it. (This is despite the fact that prominent atheists such as Professor Daniel Dennett also believe in free will).
The tribal truth fallacy lies not in the falsity of beliefs about mask wearing, climate change, GMOs, vaccines or free will per se; but in the basis for these beliefs being identification with one’s own tribe or opposition to a rival tribe.
Currently, there are three important issues on which there is scientific consensus but controversy among laypeople: climate change, biological evolution and childhood vaccination. On all three issues, prominentmembers of the Trump administration, including the president, have lined up against the conclusions of research.
This widespread rejection of scientific findings presents a perplexing puzzle to those of us who value an evidence-based approach to knowledge and policy.
Yet many science deniers do cite empirical evidence. The problem is that they do so in invalid, misleading ways. Psychological research illuminates these ways.
No shades of gray
As a psychotherapist, I see a striking parallel between a type of thinking involved in many mental health disturbances and the reasoning behind science denial. As I explain in my book “Psychotherapeutic Diagrams,” dichotomous thinking, also called black-and-white and all-or-none thinking, is a factor in depression, anxiety, aggression and, especially, borderline personality disorder.
In this type of cognition, a spectrum of possibilities is divided into two parts, with a blurring of distinctions within those categories. Shades of gray are missed; everything is considered either black or white. Dichotomous thinking is not always or inevitably wrong, but it is a poor tool for understanding complicated realities because these usually involve spectrums of possibilities, not binaries.
Spectrums are sometimes split in very asymmetric ways, with one-half of the binary much larger than the other. For example, perfectionists categorize their work as either perfect or unsatisfactory; good and very good outcomes are lumped together with poor ones in the unsatisfactory category. In borderline personality disorder, relationship partners are perceived as either all good or all bad, so one hurtful behavior catapults the partner from the good to the bad category. It’s like a pass/fail grading system in which 100 percent correct earns a P and everything else gets an F.
In my observations, I see science deniers engage in dichotomous thinking about truth claims. In evaluating the evidence for a hypothesis or theory, they divide the spectrum of possibilities into two unequal parts: perfect certainty and inconclusive controversy. Any bit of data that does not support a theory is misunderstood to mean that the formulation is fundamentally in doubt, regardless of the amount of supportive evidence.
Similarly, deniers perceive the spectrum of scientific agreement as divided into two unequal parts: perfect consensus and no consensus at all. Any departure from 100 percent agreement is categorized as a lack of agreement, which is misinterpreted as indicating fundamental controversy in the field.
There is no ‘proof’ in science
In my view, science deniers misapply the concept of “proof.”
Proof exists in mathematics and logic but not in science. Research builds knowledge in progressive increments. As empirical evidence accumulates, there are more and more accurate approximations of ultimate truth but no final end point to the process. Deniers exploit the distinction between proof and compelling evidence by categorizing empirically well-supported ideas as “unproven.” Such statements are technically correct but extremely misleading, because there are no proven ideas in science, and evidence-based ideas are the best guides for action we have.
I have observed deniers use a three-step strategy to mislead the scientifically unsophisticated. First, they cite areas of uncertainty or controversy, no matter how minor, within the body of research that invalidates their desired course of action. Second, they categorize the overall scientific status of that body of research as uncertain and controversial. Finally, deniers advocate proceeding as if the research did not exist.
For example, climate change skeptics jump from the realization that we do not completely understand all climate-related variables to the inference that we have no reliable knowledge at all. Similarly, they give equal weight to the 97 percent of climate scientists who believe in human-caused global warming and the 3 percent who do not, even though many of the latter receive support from the fossil fuels industry.
This same type of thinking can be seen among creationists. They seem to misinterpret any limitation or flux in evolutionary theory to mean that the validity of this body of research is fundamentally in doubt. For example, the biologist James Shapiro (no relation) discovered a cellular mechanism of genomic change that Darwin did not know about. Shapiro views his research as adding to evolutionary theory, not upending it. Nonetheless, his discovery and others like it, refracted through the lens of dichotomous thinking, result in articles with titles like, “Scientists Confirm: Darwinism Is Broken” by Paul Nelson and David Klinghoffer of the Discovery Institute, which promotes the theory of “intelligent design.” Shapiro insists that his research provides no support for intelligent design, but proponents of this pseudoscience repeatedly cite his work as if it does.
For his part, Trump engages in dichotomous thinking about the possibility of a link between childhood vaccinations and autism. Despite exhaustive research and the consensus of all major medical organizations that no link exists, Trump has often cited a link between vaccines and autism and he advocates changing the standard vaccination protocol to protect against this nonexistent danger.
There is a vast gulf between perfect knowledge and total ignorance, and we live most of our lives in this gulf. Informed decision-making in the real world can never be perfectly informed, but responding to the inevitable uncertainties by ignoring the best available evidence is no substitute for the imperfect approach to knowledge called science.
But what does it even mean to speak of “scientific evidence”?
The art of persuasion
History reveals that scientific forms of evidence have rarely, if ever, been detached from rhetoric. In fact, the very idea of evidence has its origins within the context of classical rhetoric, the art of persuasion.
Our modern term originates from the ancient Greek ἐνάργεια (enargeia), a rhetorical device whereby words were used to enhance the truth of a speech through constructing a vivid and evocative image of the things related.
Far from independent and objective, enargeia depended entirely on the abilities of the orator.
In the hands of an exceptional orator – such as the ancient Greek poet Homer – it could be deployed so effectively that listeners came to believe themselves eyewitnesses to what was being described.
Before the court
Aware of its utility to the law, the Roman statesman Marcus Tullius Cicero brought enargeia into forensic rhetoric during the 1st century BCE, translating it into Latin as evidentia.
For Roman orators such as Cicero and, in the 1st century AD, Marcus Fabius Quintilian, evidentia was particularly well suited to the courtroom.
Here it could be used to paint the scene of a grisly murder: The blood, the groans, the last breath of the dying victim. Recounting the scene of a murder in vivid language brought it immediately before the mind’s eye, affording it the quality of evidentia (“evidentness”) in the process.
Such detail was of paramount importance. The more detail the orator could furnish, the more likely it was that his account would convince the jury of its truth.
From its inception, then, enargeia/evidentia was a device that was used by one person to convince another about a particular reality that might not otherwise be evident. There was an art to it.
We can be forgiven for forgetting that the idea of scientific evidence originates in the art of rhetoric, for early modern scientists went to considerable lengths to disassociate the idea from its classical past.
Through their efforts, the meaning of evidence was shifted from a rhetorical device to denote something sufficiently self-evident that inferences could be drawn from it.
Adopting the English translation of evidentia from the common law in the 1660s, Robert Boyle (1627-1691), Robert Hooke (1635-1703) and other practitioners of the new science situated “evidence” as the end result of unbiased observation and experimentation.
Unlike classical evidentia, scientific “evidence” was objective because it spoke for itself. As the motto of the newly-minted Royal Society of London – nullius in verba – stressed, its members were to “take no one’s word for it”.
Just like forensic evidentia, the truth of scientific evidence was based on its immediacy.
Hooke’s microscope, to give an example, permitted the viewer to witness first-hand the compound eye of the dronefly in such marvellous detail as to leave him or her without any doubt of its reality – a “see-for-yourself” mindset that was crucial to the success of science.
Yet in practice, because most people were unable to peer through the eyepiece of a microscope, the evidence Hooke collected remained largely reliant on testimony.
Whether one accepted Hooke’s evidence for a previously unknown, microscopic world depended more on the painstakingly detailed illustrations and descriptions he gave in his 1665 Micrographia than the observations themselves.
Contrary to the Royal Society’s motto, it was not the things themselves but the way in which they were presented – and their presentation by a morally upstanding expert – that ultimately did most of the convincing.
The same holds true today. The invisible structures, processes and interactions that scientists train for years to observe remain unobservable to most people.
In marked contrast to the complex evidence for climate change, Trump positions his tweets as common sense evidence against it. In this, immediacy is on his side. Freezing weather is readily apparent to everyone, not just to scientists.
Trump’s followers are made direct witnesses to the truth of climate change by appeal to that which is most evident to them and thus, by implication, that which is the best evidence.
Even if a record cold and snow spell is not, in reality, evidence against climate change, its capacity to convince is greater because, unlike genuine evidence for climate change, it is both simple and immediate.
Evidence for climate change, on the other hand, requires trust in the scientific community, a trust that is meant to offset its lack of immediacy and which asks us to suspend our senses.
Trump’s tweets aim to delegitimise this trust, empowering his followers by telling them to trust the evidence of their own senses, their own expertise.
As scientific evidence has become increasingly complex, so too has the idea of “clear scientific evidence” become an oxymoron. If anything, Trump’s assault on climate change should serve as a reminder that making scientific evidence evident enough to convince the public is an art that needs to be embraced.
Scientific evidence can’t always be expected to speak for itself.
National Party MP George Christensen has invited other Nationals to join the recently formed pro-coal “Monash Forum”. But is coal in the best interests of their rural constituents, particularly farmers?
Farmers stand to lose from any weakening of the government’s climate change policies. That is why farmers and their political representatives should be concerned about a current review of the government’s greenhouse gas reduction policy.
What is at stake here is the strange-sounding idea of carbon farming. To explain this idea takes several steps, so bear with me.
The policy under review is a legacy of the Abbott era. As prime minister, Tony Abbott abolished the carbon tax and replaced it with an Emissions Reduction Fund (ERF). The ERF was to be used to pay businesses to reduce their carbon emissions, or to capture and sequester (store) carbon dioxide already in the atmosphere.
regenerating native forest on previously cleared land
changed farming practices to allow for crop stubble retention
capturing and destroying the methane from effluent waste at piggeries.
How does carbon farming work?
To make it all work, the government first created the system of Australian Carbon Credit Units (ACCUs). This system commodifies the outputs of carbon farming, so these can be traded.
In this system, a carbon farmer must show either a reduction in emissions, or carbon sequestration (or ideally both), according to clearly specified criteria. The government will then issue (free of charge) one credit for every tonne of carbon dioxide (CO₂) – or CO₂ equivalent – abated in this way. Farmers can then sell these credits, thus receiving a direct financial return for their efforts.
The primary buyer of ACCUs at the moment is the government, via its Emissions Reduction Fund. Farmers (individually or as collectives) who want to embark on carbon farming projects are asked to nominate a price they would need to make it profitable for them to go ahead with the project. Through a reverse auction, the fund selects the lowest-price proposals.
In this way, the government gets the greatest carbon abatement for the least money. Successful bidders embark on their projects knowing that they have a guaranteed price for their carbon abatement outcomes. There is nothing magical or mystical about it. It is simply the price at which the buyer and sellers of carbon credits find it mutually advantageous to do business.
The average price paid at the last auction round was A$12 per tonne of CO₂ abated. This is the current carbon price in this particular market.
The Safeguard Mechanism
A second potential set of buyers of carbon credits was created by the Safeguard Mechanism, introduced by the Abbott government. This caps emissions from big industrial emitters in order to to ensure that abatement achieved by the ERF is not offset or cancelled out.
The cap is set at whatever the maximum emission rate from the emitter has been. So it is not designed to reduce emissions from these big emitters, but simply to hold them to current levels.
This policy is now beginning to bite. The government has just announced that in the first period for which the policy has been in effect, some 16 large emitters were in excess and had to buy 448,000 carbon credits to remain in compliance. Among the biggest buyers were:
Anglo Coal’s Capcoal mining operations
Glencore’s Tahmoor Coal
Rio Tinto’s Alcan Gove aluminium operations
BHP Billiton Mitsubishi Coal/BM Alliance.
These companies bought their credits from carbon farmers who abated more carbon then they had calculated, and so had a surplus left over for sale.
But what is most interesting is the price that excess emitters were willing to pay for the surplus credits. Most of the sales were in the region of $14-15 per tonne (T), but the price rose to $17-18/T as the deadline approached.
This means that the price spiked at 50% higher than the most recent ERF auction price of $12/T.
Commentators describe this as a secondary market, and the price in this market is exciting news for carbon farmers. According to Australian Carbon Market Institute CEO Peter Castellas, “Australia now has a functioning carbon market.” Carbon farmers – who make up an increasing proportion of the Nationals’ constituency – will do well if this market expands.
One way to develop the market would be to slowly lower the caps on big emitters so they must either buy more carbon credits or find ways to reduce their own emissions.
From this point of view, there is good reason to progressively and predictably reduce the emissions allowed under the Safeguard Mechanism.
The current review
Here’s where we get to the current review. As already noted, the Safeguard Mechanism does not seek to reduce emissions from big emitters. In fact, it allows for an increase in emissions to accommodate business growth. Nevertheless, big emitters are still unhappy.
The government’s review is a response to business concerns. An initial consultation paper has proposed making it easier to raise the cap on a company’s emissions as its activity grows.
If the rules are altered in this way, the demand for carbon credits may stall, and even decline, bringing to an end to this promising new source of revenue for farmers.
That is why members of parliament with rural constituencies should take note. Rural MPs should not sit by and allow the government to respond to the interests of the coal industry and other lobby groups.
Carbon farming depends on reducing the caps under the Safeguard Mechanism, not raising them. This would also be a step in the direction of achieving the emissions reduction target to which Australia agreed at the Paris meetings in 2015.
Australia has national environment laws – the Environment Protection Biodiversity Conservation Act (EPBC Act). Yet given the staggering rates of land clearing taking place, resulting in the extinction and endangerment of plants and animals in Australia, these laws are clearly not working.
About 395,000 hectares of regrowth and old growth vegetation were cleared during 2015-16 in Queensland. Australia is set to clear up to 3 million hectares of native forest by 2030, and more than 1,800 plant and animal species are currently listed as threatened nationally.
When the EPBC Act was first implemented in 1999, the idea was for it to provide reinforced federal environmental protection to areas of national environmental significance. But in reality, many projects that come within the ambit of the Act are not rigorously evaluated for their environmental impact.
Why isn’t the EPBC Act working?
Land clearing was listed in the 2001 and 2006 State of the Environment Reports as one of the greatest threats to biodiversity.
Deforestation and excessive land clearing fundamentally impacts existing biodiversity, damages fragile ecosystems, destroys wildlife habitat, and increases greenhouse gas emissions. In Queensland, where much of the land clearing is taking place, the state law (Vegetation Management Act) is not strong enough to diminish incentives for land clearing. Yet the national environmental laws have not provided greater protection.
There are several reasons for this. While land clearing is indirectly regulated by the EPBC Act due to the significant impact it can have on the environment, land clearing is not directly addressed by the EPBC Act.
As it stands, land clearing will only attract EPBC Act application where it can be established that it impacts a directly protected entity such as a World Heritage area, Ramsar wetland, threatened species, ecological community, or migratory species. If this connection cannot be established, no environmental assessment under the EPBC Act will occur.
Even where projects do attract the application of the EPBC Act, its capacity to advance best practice environmental impact assessment is highly questionable. One of the biggest problems is that the process of assessment is insufficiently robust.
This problem is evident in other environmental issues too. Where a bilateral state and federal assessment is approved, as was the case with the Adani coalmine, the federal department often relies on state counterparts to undertake a thorough environmental assessment. Many of the proposals evaluated by state departments are assessed with reference to the least onerous environmental impact assessment available.
This documentation is generally prepared by the project proponent. Unsurprisingly, as a consequence, many of the projects that are evaluated under the EPBC Act are approved, subject to the imposition of environmental conditions. This means the environmental conditions need to be carefully monitored if environmental protection is to be optimised.
This creates a new set of problems. Where a breach is alleged, it must be proved and appropriate sanctions enforced. In reality, this rarely happens, and the sanctions that are imposed can be woefully inadequate. For example, Adani was fined A$12,000 for breaching an environmental condition relating to the release of coalwater in Abbott Point coal terminal, which flowed into the fragile Caley Valley Wetlands.
The substantive problem with the EPBC Act is that its implementation is subject to departmental discretion and therefore the vagaries of government administration. This is particularly problematic given the political nature of many of these decision-making processes.
Lack of rigorous scrutiny
In circumstances where, for example, there is a need to challenge the approval of a resource title in light of its environmental consequences, the EPBC Act relies heavily on environmental groups or other third parties to scrutinise the federal decision-making process.
For example, the Australian Conservation Foundation took strong action in challenging the issuance of the mining licence for Adani’s proposed Carmichael coal mine. It argued the endangered species and climate change impacts were insufficiently taken into account by the then Environment Minister Greg Hunt in exercising discretion under the EPBC Act.
The case was dismissed because the Federal Court found that this decision was authorised by the discretions included within the EPBC Act. The minister was therefore within his power to decide not to take account of the climate change impacts of such a vast new coalmine. This is concerning given the profound impact that climate change can have upon fragile ecologies in areas of national environmental significance.
These findings indicate a lack of preparedness by the federal minister to accept a causal connection between climate change and domestic coal production, and to focus on narrow jurisdictional boundaries and strict domestic obligations. It also strongly highlights the deficiencies of our national environment act because the existing triggers do not address some of the most important environmental concerns of the modern world.
New environment laws urgently needed
Climate change is almost universally accepted as one the most serious environmental threats. Yet the EPBC Act does not include a climate change trigger (or a land clearing trigger, as discussed above).
This means these key threats to Australia’s environment will not be protected by EPBC Act. They may attract the EPBC Act indirectly, but only if it can be established that they raise a different trigger that is listed under the Act. This calls into question the capacity of our national environment laws to truly protect areas of national environmental significance.
In order to reverse unacceptable rates of land clearing, preserve ecosystems and habitats and diminish greenhouse gas emissions, a new framework for our national environment act is urgently needed.
Two cities on opposing continents, Santiago and Cape Town, have been brought to their knees by events at opposing ends of the climate spectrum: flood and drought.
The taps ran dry for Santiago’s 5 million inhabitants in early 2017, due to contamination of supplies by a massive rainfall event. And now Cape Town is heading towards “day zero” on May 11, after which residents will have to collect their drinking water from distribution points.
In many of these places governments have tried to hedge their bets by turning to increasingly expensive and energy-ravenous ways to ensure supply, such as desalination plants and bulk water transfers. These two elements have come together in Victoria with the pumping of desalinated water 150km from a treatment plant at Wonthaggi, on the coast, to the Cardinia Reservoir, which is 167m above sea level.
But while providing clean water is a non-negotiable necessity, these strategies also risk delivering a blowout in greenhouse emissions.
Climate change puts many new pressures on water quality. Besides the effects of floods and droughts, temperature increases can boost evaporation and promote the growth of toxic algae, while catchments can be contaminated by bushfires.
At the height of the Millennium Drought, household water savings and restrictions lowered volumes in sewers (by up to 40% in Brisbane, for example). The resulting increase in salt concentrations put extra pressure on wastewater treatment and reclamation..
The energy needed to pump, treat, distribute and heat water – and then to convey, pump, reclaim or discharge it as effluent, and to move biosolids – is often overlooked. Many blueprints for zero-carbon cities underplay or neglect entirely the carbon footprint of water supply and sewage treatment.
Some analyses only consider the energy footprint of domestic water heating, rather than the water sector as a whole – which is rather like trying to calculate the carbon footprint of the livestock industry by only looking at cooking.
Yet the growing challenge of delivering a reliable and safe water supply means that energy use is growing. The United States, for example, experienced a 39% increase in electricity usage for drinking water supply and treatment, and a 74% increase for wastewater treatment over the period 1996-2013, in spite of improvements in energy efficiency.
As climate change puts yet more pressure on water infrastructure, responses such as desalination plants and long-distance piping threaten to add even more to this energy burden. The water industry will increasingly be both a contributor to and a casualty of climate change.
How much energy individual utilities are actually using, either in Australia or worldwide, will vary widely according to the source of supply – such as rivers, groundwater or mountain dams – and whether gravity feeds are possible for freshwater and sewage (Melbourne shapes up well here, for example, whereas the Gold Coast doesn’t), as well as factors such as the level of treatment, and whether or not measures such as desalination or bulk transfers are in place.
One option would be for water facilities to take themselves at least partly “off-grid”, by installing large amounts of solar panels, onsite wind turbines, or Tesla-style batteries (a few plants also harness biogas). Treatment plants are not exactly bereft of flat surfaces – such as roofs, grounds or even ponds – an opportunity seized upon by South Australian Water.
But this is a large undertaking, and the alternative – waiting for the grid itself to become largely based on renewables – will take a long time.
A 2012 study found large variations in pump efficiency between water facilities in different local authorities across Australia. Clearly there is untapped scope for collaboration and knowledge-sharing in our water sector, as is done in Spain and Germany, where water utilities have integrated with municipal waste services, and in the United States, where the water and power sectors have gone into partnership in many places.
The developing world
Climate change and population growth are seriously affecting cities in middle-band and developing countries, and the overall outlook is grim. Many places, such as Mexico City, already have serious water contamination problems. Indeed, in developing nations these problems are worsened by existing water quality issues. Only one-third of wastewater is treated to secondary standard in Asia, less than half of that in Latin America and the Caribbean, and a minute amount in Africa.
The transfer of know-how to these places is critical to reaching clean energy transitions. Nations making the energy transition – especially China, the world’s largest greenhouse emitter – need to take just as much care to ensure they avoid a carbon blowout as they transition to clean water too.
Just as in the electricity sector, carbon pricing can potentially provide a valuable incentive for utilities to improve their environmental performance. If utilities were monitored on the amount of electricity used per kilolitre of water processed, and then rewarded (or penalised) accordingly, it would encourage the entire sector to up its game, from water supply all the way through to sewage treatment.
Water is a must for city-dwellers – a fact that Cape Town’s officials are now nervously contemplating. It would be helpful for the industry to participate in the strategic planning and land-use debates that affect its energy budgets, and for its emissions (and emissions reductions) to be measured accurately.
In this way the water industry can become an influential participant in decarbonising our cities, rather than just a passive player.
This article is based on a journal article (in press) co-authored by David Smith, former water quality manager for South East Water, Melbourne.
In early 2016, we heard that the reef had suffered the worst bleaching ever recorded. Surveys published in June that year estimated that 93% of coral on the vast northern section of the reef was bleached, and 22% had already been killed.
Coral reefs are complex ecosystems that are affected by many factors. Changes in sea surface temperatures, rainfall, cloudiness, agricultural runoff, or water quality can affect a reef’s health and resilience to stress.
Early analysis of the 2016 bleaching suggested that the Great Barrier Reef was suffering from thermal stress brought on by human-caused climate change.
Our study took a new and comprehensive approach to examine these multiple climatic and environmental influences.
We set out to answer the crucial question: could anything else have bleached the Great Barrier Reef, besides human-induced climate change?
The results were clear. Using a suite of climate models, we found that the significant warming of the Coral Sea region was likely caused by greenhouse gases from human activities. This warming was the primary cause of the extreme 2016 bleaching episode.
Our study showed that although the 2016 El Niño probably also contributed to the bleaching, this was a secondary contributor to the corals’ thermal stress. The major factor was the increase in temperatures because of climate change.
We next analysed other environmental data. Previous research has found that corals at sites with better water quality (that is, lower concentrations of pollution particles) are more resilient and less prone to bleaching.
Pollution data used in our study show that water quality in 2016 may have been better than in previous bleaching years. This means that the Great Barrier Reef should have been at lower risk of bleaching compared to long-term average conditions, all else being equal. Instead, record bleaching hit the reef as a result of the warming temperature trend.
The final part of our investigation involved comparing the conditions behind the record 2016 bleaching with those seen in previous mass bleaching episodes on the Great Barrier Reef, in 1997-98 and 2010-11.
When we analysed these previous events on the Reef, we found very different factors at play.
In 1997-98 the bleaching coincided with a very strong El Niño event. Although an El Niño event also occurred in 2016, the two were very different in terms of the distribution of unusually warm waters, particularly in the eastern equatorial Pacific. In 1997-98, the primary cause of the bleaching – which was less severe than in 2016 – was El Niño.
In 2010-11, the health of the Great Barrier Reef was impaired by runoff. That summer brought record high rainfall to eastern Australia, causing widespread flooding across Queensland. As a result of the discharge of freshwater onto the reef reducing the salinity, bleaching occurred.
There have been many reports in recent years warning of trouble for the Great Barrier Reef. Sadly, our study is yet another warning about the reef’s future – perhaps the most comprehensive warning yet. It tells us that the 2016 bleaching differed from previous mass bleaching events because it was driven primarily by human-induced climate warming.
This puts the Great Barrier Reef in grave danger of future bleaching from further greenhouse warming. The local environmental factors that have previously helped to protect our reefs, such as good water quality, will become less and less able to safeguard corals as the oceans warm.
Now we need to take immediate action to reduce greenhouse gas emissions and limit further warming. Without these steps, there is simply no future for our Great Barrier Reef.
Melting of Antarctica’s ice can trigger rapid warming on the other side of the planet, according to our new research which details how just such an abrupt climate event happened 30,000 years ago, in which the North Atlantic region warmed dramatically.
This idea of “tipping points” in Earth’s system has had something of a bad rap ever since the 2004 blockbuster The Day After Tomorrow purportedly showed how melting polar ice can trigger all manner of global changes.
But while the movie certainly exaggerated the speed and severity of abrupt climate change, we do know that many natural systems are vulnerable to being pushed into different modes of operation. The melting of Greenland’s ice sheet, the retreat of Arctic summer sea ice, and the collapse of the global ocean circulation are all examples of potential vulnerability in a future, warmer world.
Of course it is notoriously hard to predict when and where elements of Earth’s system will abruptly tip into a different state. A key limitation is that historical climate records are often too short to test the skill of our computer models used to predict future environmental change, hampering our ability to plan for potential abrupt changes.
One of the most important sources of information on past climate tipping points are the kilometre-long cores of ice drilled from the Greenland and Antarctic ice sheets, which preserve exquisitely detailed information stretching back up to 800,000 years.
The Greenland ice cores record massive, millennial-scale swings in temperature that have occurred across the North Atlantic region over the past 90,000 years. The scale of these swings is staggering: in some cases temperatures rose by 16℃ in just a few decades or even years.
Twenty-five of these major so-called Dansgaard–Oeschger (D-O) warming events have been identified. These abrupt swings in temperature happened too quickly to have been caused by Earth’s slowly changing orbit around the Sun. Fascinatingly, when ice cores from Antarctica are compared with those from Greenland, we see a “seesaw” relationship: when it warms in the north, the south cools, and vice versa.
Attempts to explain the cause of this bipolar seesaw have traditionally focused on the North Atlantic region, and include melting ice sheets, changes in ocean circulation or wind patterns.
But as our new research shows, these might not be the only cause of D-O events.
We know that there have been major collapses of the Antarctic ice sheet in the past, raising the possibility that these may have tipped one or more parts of the Earth system into a different state. To investigate this idea, we analysed an ancient New Zealand kauri tree that was extracted from a peat swamp near Dargaville, Northland, and which lived between 29,000 and 31,000 years ago.
Through accurate dating, we know that this tree lived through a short D-O event, during which (as explained above) temperatures in the Northern Hemisphere would have risen. Importantly, the unique pattern of atmospheric radioactive carbon (or carbon-14) found in the tree rings allowed us to identify similar changes preserved in climate records from ocean and ice cores (the latter using beryllium-10, an isotope formed by similar processes to carbon-14). This tree thus allows us to compare directly what the climate was doing during a D-O event beyond the polar regions, providing a global picture.
The extraordinary thing we discovered is that the warm D-O event coincided with a 400-year period of surface cooling in the south and a major retreat of Antarctic ice.
When we searched through other climate records for more information about what was happening at the time, we found no evidence of a change in ocean circulation. Instead we found a collapse in the rain-bearing Pacific trade winds over tropical northeast Australia that was coincident with the 400-year southern cooling.
To explore how melting Antarctic ice might cause such dramatic change in the global climate, we used a climate model to simulate the release of large volumes of freshwater into the Southern Ocean. The model simulations all showed the same response, in agreement with our climate reconstructions: regardless of the amount of freshwater released into the Southern Ocean, the surface waters of the tropical Pacific nevertheless warmed, causing changes to wind patterns that in turn triggered the North Atlantic to warm too.
Future work is now focusing on what caused the Antarctic ice sheets to retreat so dramatically. Regardless of how it happened, it looks like melting ice in the south can drive abrupt global change, something of which we should be aware in a future warmer world.
There was a brief period of consensus ushered in by John Howard’s belated realisation in 2006 that a price had to be put on carbon dioxide emissions. But by December 2009 the Nationals, and enough Liberals, had decided that this was a mistake, and have opposed explicit carbon pricing ever since.
But the Liberal Party’s tussles over climate and energy policy (as distinct from denying the science itself) go back even further – some 30 years.
Early days and ‘early’ action
It’s hard to believe it now, but the Liberal Party took a stronger emissions target than Labor to the 1990 Federal election. Yet green-minded voters were not persuaded, and Labor squeaked home with their support. After that episode the Liberals largely gave on courting green voters, and under new leader John Hewson the party tacked right. Ironically, considering Hewson’s climate advocacy today, back then his Fightback! policy was as silent on climate change as it was on the price of birthday cakes.
In his excellent 2007 book High and Dry, former Liberal speech writer Guy Pearse recounts how in the mid-1990s he contacted the Australian Conservation Foundation, offering to to canvass Coalition MPs to “find the most promising areas of common ground” on which to work when the party returned to government. The ACF was “enthusiastic, if a little bemused at the novelty of a Liberal wanting to work with them”. Most Liberal MPs – including future environment minister Robert Hill and future prime minister Tony Abbott – were “strongly supportive” of the idea. But others (Pearse names Eric Abetz and Peter McGauran) were “paranoid that some kind of trap was being laid”. Nothing came of it.
Elected in 1996, Howard continued the staunch hostility to the United Nations climate negotiations that his Labor predecessor Paul Keating had begun. Not all businessmen were happy. Leading up to the crucial Kyoto summit in 1997, the Sydney Morning Herald reported how a “delegation of scientists and financiers” led by Howard’s local party branch manager Robert Vincin and Liberal Party grandee Sir John Carrick lobbied the prime minister to take a more progressive approach. Howard did not bend.
Howard stayed unmoved until 2006 when, facing a perfect storm of rising public climate awareness and spiralling poll numbers, he finally relented. Earlier that year a group of businesses convened by the Australian Conservation Foundation produced a report titled The Early Case for Business Action. “Early” is debatable, given that climate change had already been a political issue since 1988, but more saliently the report tentatively suggested introducing a carbon price. And Howard finally relented.
The carbon wars
The ensuing ten years after Kevin Rudd’s defeat of Howard don’t need much recapping here (go here for all the details). But one interesting phenomenon that has emerged from the policy wreckage is the emergence of some very unusual coalitions to beg for certainty.
Then, after the seminal South Australia blackout last September, a surprisingly diverse group of industry and consumer bodies – the Australian Energy Council, Australian Industry Group, Business Council of Australia, Clean Energy Council, Energy Users Association, Energy Consumers Australia, Energy Networks Association and Energy Efficiency Council – called on federal and state energy ministers to “work together to craft a cooperative and strategic response to the transformation underway in Australia’s energy system”.
It’s in this light that the new Conservatives for Conservation lobbying effort should be seen. Its spearhead Kristina Photios surely knows she has no chance of converting the committed denialists, but she can chip away at the waverers currently giving them comfort and power.
Questions on notice
Of course, there are always cultural (or even psychological) issues, but you’d think that conservation would be a no-brainer for conservatives (the clue should be in the name).
There are a few questions, of course (with my answers in brackets).
Where were all the people who are now calling for policy certainty back in 2011 when Tony Abbott was declaring his oath to kill off the carbon tax? (They were AWOL.)
Will any business show any interest in building a new coal-fired power station? (No.)
Is renewable energy technology now advanced enough for them to make serious money? (We shall see.)
Can we make up for lost time in our emissions reductions? (No, and we have already ensured more climate misery than there would have been with genuinely early climate action.)
Will the Liberals further water down the Clean Energy Target proposal? (Probably.)
What will Tony Abbott say to UK climate sceptic think tank the Global Warming Policy Foundation when he gives a speech on October 6? (Who knows –
grab your popcorn!).
What will happen to the Liberals in the medium term? (Who knows, but Michelle Grattan of this parish has some intriguing ideas.)
Are there reasons to be cheerful? (Renewable energy journalist Ketan Joshi thinks so.)
Perhaps the last word on this issue should go to John Hewson, who noted last year:
The “right” love to speak of the debt and deficit problem as a form of “intergenerational theft”, yet they fail to see the climate challenge in the same terms, even though the consequences of failing to address it substantively, and as a matter of urgency, would dwarf that of the debt problem. The “right” is simply “wrong”. It’s political opportunism of the worst sort, and their children and grandchildren will pay the price.
I’ve wanted to be a scientist since I was five years old.
My idea of a scientist was someone in a lab, making hypotheses and testing theories. We often think of science only as a linear, objective process. This is also the way that science is presented in peer reviewed journal articles – a study begins with a research question or hypothesis, followed by methods, results and conclusions.
It turns out that my work now as a climate scientist doesn’t quite gel with the way we typically talk about science and how science works.
Climate change, and doing climate change research, has changed the way I see and do science. Here are five points that explain why.
Falsifiability is the idea that an assertion can be shown to be false by an experiment or an observation, and is critical to distinctions between “true science” and “pseudoscience”.
Climate models are important and complex tools for understanding the climate system. Are climate models falsifiable? Are they science? A test of falsifiability requires a model test or climate observation that shows global warming caused by increased human-produced greenhouse gases is untrue. It is difficult to propose a test of climate models in advance that is falsifiable.
This difficulty doesn’t mean that climate models or climate science are invalid or untrustworthy. Climate models are carefully developed and evaluated based on their ability to accurately reproduce observed climate trends and processes. This is why climatologists have confidence in them as scientific tools, not because of ideas around falsifiability.
2. There’s lots of ways to interpret data
Climate research is messy. I spent four years of my PhD reconstructing past changes in Australian and Indonesian rainfall over many thousands of years. Reconstructing the past is inherently problematic. It is riddled with uncertainty and subject to our individual interpretations.
During my PhD, I submitted a paper for publication detailing an interpretation of changes in Indonesian climates, derived from a stalagmite that formed deep in a cave.
My coauthors had disparate views about what, in particular, this stalagmite was telling us. Then, when my paper was returned from the process of peer review, seemingly in shreds, it turns out the two reviewers themselves had directly opposing views about the record.
What happens when everyone who looks at data has a different idea about what it means? (The published paper reflects a range of different viewpoints).
Another example of ambiguity emerged around the discussion of the hiatus in global warming. This was the temporary slowdown in the rate of global warming at the Earth’s surface occurring roughly over the 15 year period since 1997. Some sceptics were adamant that this was unequivocal proof that the world was not warming at all and that global warming was unfounded.
There was an avalanche of academic interest in the warming slowdown. It was attributed to a multitude of causes, including deep ocean processes, aerosols, measurement error and the end of ozone depletion.
Ambiguity and uncertainty are key parts of the natural world, and scientific exploration of it.
3. Sometimes the scientist matters as well as the results
I regularly present my scientific results at public lectures or community events. I used to show a photo depicting a Tasmanian family sheltering under a pier from a fire front. The sky is suffused with heat. In the ocean, a grandmother holds two children while their sister helps her brother cling to underside of the pier.
After a few talks, I had to remove the photo from my PowerPoint presentation because each time I turned around to discuss it, it would make me teary. I felt so strongly that the year we were living was a chilling taste of our world to come.
Just outside of Sydney, tinderbox conditions occurred in early spring of 2013, following a dry, warm winter. Bushfires raged far too early in the season. I was frightened of a world 1°C hotter than now (regardless of what the equilibrium climate sensitivity turns out to be).
At public lectures and community events, people want to know that I am frightened about bushfires. They want to know that I am concerned about the vulnerability of our elderly to increasing summer heat stress. People want to know that, among everything else, I remain optimistic about our collective resilience and desire to care for each other.
Communicating how we connect with scientific results is also important part of the role of climate scientists. That photo of the family who survived the Tasmanian bushfire is now back in my presentations.
4. Society matters too
In November 2009, computer servers at the University of East Anglia were illegally hacked and email correspondence was stolen.
A selection of these emails was published publicly, focusing on quotes that purported to reveal dishonest practices that promoted the myth of global warming. The “climategate” scientists were exhaustively cleared of wrongdoing.
On the surface, the climategate emails were an unpleasant but unremarkable event. But delving a little deeper, this can be seen as a significant turning point in society’s expectations of science.
While numerous fastidious reviews of the scientists cleared them of wrongdoing, the strong and ongoing public interest in this matter demonstrates that society wants to know how science works, and who “does” science.
There is a great desire for public connection with the processes of science and the outcomes of scientific pursuits. The public is not necessarily satisfied by scientists working in universities and publishing their finding in articles obscured by pay walls, which cannot be publicly accessed.
A greater transparency of science is required. This is already taking off, with scientists communicating broadly through social and mainstream media and publishing in open access journals.
Enlisting non-expert volunteers allows researchers to investigate otherwise very difficult problems, for example when the research would have been financially and logistically impossible without citizen participation.
The OzDocs project involved volunteers digitising early records of Australian weather from weather journals, government gazettes, newspapers and our earliest observatories. This project provided a better understanding of the climate history of southeastern Australia.
Personal computers also provide another great tool for citizen collaborators. In one ongoing project, climate scientists conduct experiments using publicly volunteered distributed computing. Participants agree to run experiments on their home or work computers and the results are fed back to the main server for analysis.
While we often think of scientists as trained experts working in labs and publishing in scholarly journals, the lines aren’t always so clear. Everyone has an opportunity to contribute to science.
My new book explores this space between the way science is discussed and the way it takes place.
This isn’t a criticism of science, which provides a useful way to explore and understand the natural world. It is a celebration of the richness, diversity and creativity of science that drives this exploration.