REALITY V THE FALSE ALARMISTS

At the 2025 Bush Summit in Ballarat, Anthony Albanese defended his government’s increasingly radical plans to decarbonise the Australian economy by invoking the science.

“The science told us that climate change was real,” he told a sceptical crowd in September. “And we are seeing more extreme weather events, and more intense weather events.”

Fearmongering about climate change has become more difficult in the wake of a recent report by the US Department of Energy titled A Critical Review of Impacts of Greenhouse Gas Emissions on the US Climate, aimed at the educated layperson.

The report dares to question the alarmist narrative: the costs of climate change are far less catastrophic than assumed, extreme weather events have not become more frequent or severe, climate change models have proved a poor guide to changes in the weather, and even US unilateral sacrifices will have little discernible impact on global outcomes.

The report’s credibility lies not only in having the institutional imprimatur of the world’s most powerful government but in the intellectual pedigree of its authors: John Christy, Judith Curry, Steven Koonin, Ross McKitrick, and Roy Spencer. Each is a veteran of climate debates, with decades of work in atmospheric science, climate modelling or economic analysis.

The authors are not “deniers”. They concur with the mainstream that greenhouse gases “exert a warming influence on the climate and weather”, a long-established theory first postulated in the late 19th century. But they dispute the attribution of most or more than half of the 1.07C of global warming since 1850 to human activity, contrary to most other government agencies.

Such a claim does not allow sufficiently for natural climate change, which has varied throughout history and long before humans could have been a factor, influenced by changes in solar activity. The authors find it implausible that such “natural external drivers” have had essentially no net impact on the warming since 1850, which is a core assumption of analysis commissioned by the UN’s Intergovernmental Panel on Climate Change.

For instance, the sharp increase in global temperatures in the past decade could be explained by “a significant reduction in planetary albedo since 2015, which has coincided with at least two years of record global warmth”. This refers to a decline in the fraction of incoming solar radiation that is reflected back into space rather than being absorbed by the planet.

The Medieval Warm Period and the Little Ice Age of the 17th and 18th centuries are two better known examples of climate change that cannot be attributed to humans. Others include a period of global cooling between 1945 and 1976, known as the Grand Hiatus, which included a 0.3C drop in ocean temperatures between about 1968 and 1972.

The notorious “hockey stick” chart, showing a rapid increase in global temperatures, hinges in part on the Great Pacific Climate Shift of 1976-77 – a natural climatic event closely associated with long-term cooling and warming phases. The shift in 1976 was the start of a period of accelerated global warming.

“When the Great Pacific Climate Shift is accounted for in climate attribution analyses since 1950, 40 per cent or more of the warming in the second half of the 20th century is attributed to natural internal variability,” the report states.

The data suggests such attribution is ridiculous: hurricanes in the US show “no statistically significant trend since 1920”, and only one of the 10 strongest on record to make landfall has occurred in the 21st century, the authors point out. Severe tornadoes have exhibited a “noticeable downward trend in the number since 1950”.

While the IPCC reports focus on temperature extremes since 1950, a longer record shows heatwaves and droughts were most pronounced in the “Dust Bowl era of the 1930s”.

“The overall reduction in numbers of both cold and hot extremes over the past century indicates a climate less prone to extremes,” the authors conclude, noting that many of the worst extreme weather and climate events in US history occurred in or before the first half of the 20th century.

The alarmist narrative around rising sea levels is not supported by observed data either, and relies on highly speculative modelling. Globally, sea levels have risen on average by little more than 20cm since 1900, or by “about two stacked pennies a year”.

Global sea levels have been rising (and falling) since time immemorial. The most recent cycle of rising sea levels began “during the period 1820-1860, well before most anthropogenic greenhouse gas emissions”. As for all the popular angst about the supposedly vanishing ice caps, the decline in the extent of Arctic sea ice (around the North Pole), which had been observed since 1980, stopped in 2007. And around the South Pole, the IPCC concedes, “there has been no significant trend in Antarctic Sea ice areas from 1979 to 2020”.

The Prime Minister’s reference to extreme weather is not even sustained by the IPCC. Of the 33 categories of “climatic impact-drivers”, the technical term for the manifestations of changing weather – such as the frequency and severity of landslides, snow, hail, wind speed, and sea levels – human behaviour, for example through emissions, has had a statistically reliable impact (with a high degree of confidence) on only five, and these did not include droughts and floods, which is what Albanese probably had in mind.

Even if the extreme weather events had become more common or severe in a statistically meaningful way, attribution would be next to impossible given the massive variability of such events.

“There are only about 130 years of reliable observational records that can be analysed statistically,” the authors write.

It is a little disconcerting to learn of the so-called ARkStorm of December 1861, which “dumped nearly 10 feet of rain in parts of California and submerged the entire Central Valley for weeks under as much as 15 feet of water”.

Untangling the contribution of humans to climate change among numerous known and unknown confounding factors is a herculean task and not one that should inspire the sorts of definitive conclusions that dominate the public debate.

Climate models have attracted a level of reverence in the public mind they do not deserve.

The several dozen that underpin the doomsday forecasts out to 2100 and beyond, that keep the public fearful and supportive of radical decarbonisation agendas, have “shown substantially more warming than the (actual) observations since 1979”, the DOE report authors write. In the early 2010s, the IPCC produced a range of potential trajectories for carbon dioxide emissions into the future, from which temperature increases could be inferred given various estimated sensitivities. The most extreme, known as RCP8.5, implies nearly 5C of warming from 1900 to 2100.

This speculative, low-probability, high-emissions scenario represents a “worst case” future trajectory. Yet “some 16,800 scientific papers published between 2010 and 2020 used the RCP8.5 scenario, with about 4500 of the articles linking RCP8.5 to the concept of business as usual”.

Perhaps the most provocative part of the DOE report focuses on the possibility that global warming and increased carbon dioxide in the air could be beneficial, a point barely addressed by the IPCC. Between a quarter and half of the Earth experienced a beneficial “greening” between 1982 and 2011, owing to the increased levels of carbon dioxide in the air.

A 2021 National Bureau of Economic Research study found carbon dioxide “emissions had boosted US crop production since 1940 by 50 to 80 per cent”. Another study, from 2023, found a “warming climate would yield positive benefits for French agriculture that were between two and 20 times larger than had previously been estimated”.

After all, plants and animals evolved under much higher levels of carbon dioxide in the past. Drawing on the work of Institute of Public Affairs adjunct fellow Peter Ridd, the DOE report demonstrates that concerns regarding the impact of higher water temperature and decreasing pH on the Great Barrier Reef are unwarranted. Recent data shows coral coverage on the reef has surged across the past decade, rather than declined, as many people mistakenly believe.

Humans even could benefit from higher overall temperatures, given extreme cold is significantly more lethal than extreme heat, a fact on which the IPCC has been silent. Public policy expert Roger Pielke Jr noted, as highlighted in the DOE report, that “losses per weather disaster as a proportion of GDP have decreased by about 80 per cent since 1980”.

The final sections of the report underscore the pointlessness, not to mention the extraordinary cost, of even the US taking drastic action to curb greenhouse emissions, which at best would elicit “undetectably small direct impacts on the global climate”. For instance, eliminating the entire stock of US combustion engine cars and trucks, an unrealistic eventuality in any case, would “retard the accumulation of CO2 in the atmosphere by a year or two over a century”. For context, the US is responsible for roughly 13 per cent of the world’s annual carbon dioxide emissions.

The DOE report also reviews economic arguments, pioneered by William Nordhaus that the costs of seeking to aggressively reduce emissions are far greater than the costs of climate change, even assuming that global emissions control can be co-ordinated at no cost.

Proponents of climate change alarmism have swiftly condemned the report. They accuse the authors of cherrypicking, misquoting peer-reviewed research, “and a general dismissal of the vast majority of decades of peer-reviewed research”.

Where does this leave the interested citizen who does not have the time to read the academic literature? It is difficult for a good-faith lay observer to arbitrate between these competing claims. One seemingly larger group of scientists gravitates towards the catastrophist narrative, while another suggests the threats are exaggerated.

Science is not democracy and the Covid pandemic, for one, illustrated starkly how wrong “consensus” experts and their models can be. Unfortunately, unlike Covid cases and deaths, predictions of climate disaster decades into the future are conveniently immune to real-time verification.

I always paid greater attention to scientists who spoke up against a consensus because of the significant professional and social costs they incurred. They must truly believe their arguments.

In contrast, supporting a mainstream narrative confers benefits rather than costs, suggesting at least some proportion of scientists would choose not to speak out against, or indeed actively support, a catastrophist narrative.

Moreover, the political dimension of climate science cannot be ignored. It is obvious the catastrophist narrative requires massive government regulation of households and business. Those inclined to more powerful and intrusive government for philosophical reasons, who tend to congregate in government agencies, might promote the mainstream narrative because of this, rather than for scientific reasons.

The eagerness with which some agencies have sought to fearmonger is telling. For instance, the National Oceanic and Atmospheric Administration in May had to publicly withdraw its so-called Billion Dollar Disaster publication, which attempted to show severe weather events were becoming more costly. It failed to normalise the series properly for changes in population exposure and wealth, which would have demonstrated in fact the opposite trend. It stretches credulity that someone in an agency of highly educated people hadn’t understood this.

Adam Creighton is a senior fellow at the Institute of Public Affairs and a former economics editor and Washington correspondent for The Australian. This is an edited extract of his article Good Reef!, which will appear in the forthcoming issue of the IPA Review, available online in November.