In 2026 climate scientists downgraded their worst-case scenario for global warming from 4.5°C to 2.7°C. This proves that their models were flawed from the outset and cannot be relied upon as indicators of where the world is headed. Fact: It’s true that scientists have now downgraded their worst-case scenario for global warming to 2.7°C, but not because their modelling was wrong. Rather, it’s because the rate of increase of greenhouse gas emissions has slowed considerably over the past 10 years, due to rapid technological change and concrete actions on the part of governments.  As recently as a decade ago it looked like fossil fuel use would continue to rise at the same pace as economic growth, leading to a disastrous outcome for the planet. Yet today, the demand for coal, gas and oil is beginning to plateau, thanks to the rapid development of solar, wind and battery storage, as well as the proliferation of electric vehicles. Back then it was also impossible to imagine the extent to which nations would act to cut their emissions. This was particularly so with China, the world’s biggest polluter, which has now become the global leader in renewable energy. Its emissions were expected to rise until at least 2030 but stabilised in 2024 and have now started to fall.  Little wonder then that the world is no longer on the trajectory predicted by the scientific community 20 years ago. Of course, this is not to say that we are to be spared the ravages of global warming. A temperature increase of 2.7°C is still going to cause serious problems for the world, but it’s not the doomsday outcome that was once feared.

So-called ‘experts’ have made ‘doomsday’ predictions in the past, and these have not come to pass. Examples include the likelihood that overpopulation would lead to mass starvation, the notion that the ‘millennium bug’ would disable computers and the fear that the nuclear arms race would lead to nuclear holocaust. Predictions about climate change will prove no different. Fact: This is faulty logic. The fact that one threat doesn’t come true doesn’t mean that others won’t. The coronavirus pandemic is an excellent example. Many prominent climate sceptics also denied the seriousness of the pandemic when it first emerged. Some of those people still don’t take it seriously.  Climate models have been amazingly accurate over the years. In 1906, Swedish physicist Svante Arrhenius estimated that a doubling of carbon dioxide in the atmosphere would result in global surface warming of about 4°C. That is amazingly close to modern day predictions – and Arrhenius had only rudimentary laboratory equipment and a slide rule to do his calculations.  Modern climate models have predicted global warming since the 1960s and have been proven remarkably accurate. In 1967, Syukuro Manabe and Richard Wetherald calculated that a doubling of CO2 would cause about 2.4°C of warming. [Manabe shared the 2021 Nobel Prize for Physics for his work in this area.] In 1981, James Hansen projected that between 1981 and 2015 the planet would warm by 0.6°, which is just 0.1° more than actual observations. Nobel Prize winner Syukuro Manabe [Source: Wikimedia Commons] In the 1970s, Manabe and Wetherald also predicted that CO2 emissions would cause the lower atmosphere to warm and the upper atmosphere to cool. Another of their predictions was that the Arctic would warm faster than the rest of the planet, in part because of decreased reflectivity due to melting ice. Both these predictions have been confirmed by scientific observation.  In 1989, Roland Stouffer, Syukuro Manabe and Kirk Brian predicted that CO2 emissions would cause the land surface to warm faster than the ocean surface – something which has subsequently proved to be true.  Even in the 1970s, when the climate had not warmed much for two decades, climate scientists were still predicting future warming, due to the physics of CO2. Time would prove them right. The climate pause of the 1950s and ‘60s was found to be due to increased particulate matter in the atmosphere. Once this was reduced by legislative action, global warming resumed. 

Computers can’t predict the weather two weeks ahead with any certainty, so how can they be relied on to predict what the Earth’s climate will be like in future decades?  Fact: This myth makes a false analogy between weather and climate, which are two different things. Weather is the state of the atmosphere at a given point in time. It covers temperature, cloud cover, air pressure, wind direction, wind speed, rain and snow. Climate, by contrast, is the average weather over a long period of time. It’s true that we can’t predict the weather more than a week in advance, but we can predict what average temperatures will likely be decades into the future, given the basic laws of physics.

Climate models used by scientists are at best imperfect, and cannot be used to predict future warming. Fact: Climate models are imperfect, as is our knowledge of the solar system, of cancer, of economics, and of many other things. No models of the real world are ever perfect, but that shouldn’t stop us from using them. Global climate models are very useful tools. As early as 1906, Svante Arrhenius was able to predict that a doubling of CO2 in the atmosphere would result in a 4°C increase in global temperatures. Climate models have improved dramatically since then and have proven remarkably accurate in their predictions. [See the next myth.]

The Intergovernmental Panel on Climate Change’s own figures show that the Earth has warmed far less than 1.3°C.  Fact: This view has arisen due to the fact that the IPCC’s temperature figures are averages and contain a significant margin of error. That margin of error is estimated to be 0.2°C above or below the stated figure of 1.3°C. While this does indeed mean that the Earth’s temperature could have risen by only 1.1°C since the second half of the 19th century, it also means it could have risen by as much as 1.5°C. In other words, it’s possible the situation is not quite as bad as we fear (albeit still bad!); but it’s also possible that it’s worse. Climate sceptics are happy to assume that the official figure is an overestimation but shirk from the possibility that it is actually the opposite. The most reliable figure we have is the one officially used by the IPCC – the global average.

If global warming is real, how could there still be record cold days? And how did the eastern United States experience a record cold snap in 2012-13? Surely there would be no such records in a warming climate. Fact: Global warming doesn’t mean there are no very cold days, just fewer of them. Weather reports in the US and Australia over the last 60 years show that the number of hot and cold records were about equal during the 1950s, 60s and 70s. Then the number of heat records started to increase and the number of cold records started to fall. Today, there are now almost twice as many hot records as cold ones.  Extreme weather bell curve [Source: Climate Commission] As for the record US cold snap in 2012-13, it was caused by changes in the Earth’s climate. Temperature increases in the Arctic have been causing movements in the jet stream – the band of strong winds near the top of the troposphere, about 10 km above the Earth’s surface. The jet stream acts like a barrier to the southward movement of frigid arctic air. In 2012, the jet stream moved south in a wave-like formation (known as the Wavy Jet Stream), taking cold Arctic weather with it. This is what produced the cold snap in the eastern US. At the same time, the western US experienced a terrible drought. 

Global warming cannot be real because some places, like Louisville Kentucky, have experienced no temperature increase at all. Fact: It’s true that some places, like Louisville, haven’t experienced a rise in temperature. Others, however, have had very large increases. The temperature in Sao Paulo, for example, has risen by about 2°C since the beginning of the 20th century – almost double the global average. Cherry picking data from individual locations doesn’t give us the big picture. We have to look at the global average. 

Temperature data is inaccurate because we don’t have good enough technology to measure the Earth’s surface, the oceans, the stratosphere or the troposphere. So, these cannot be relied on as indicators of global warming. Fact: First, let’s deal with the slight fall in global temperatures that occurred in the 1950s and 60s. This was caused by increased particulate matter (sulfate aerosols) in the atmosphere, due to unregulated industrialisation. This particulate matter reflected some of the sun’s rays away from the Earth, causing a small amount of cooling. When, for health reasons, nations introduced laws in the 1970s mandating a reduction in industrial pollution, the quantity of particulate matter decreased significantly, and global warming resumed as predicted. [It should be noted that increased particulate matter resulting from greater volcanic activity after 1257 AD is believed to have been the main factor triggering the so-called ‘Little Ice Age’ (1450-1850 AD), which caused a noticeable drop in temperatures in the Northern Hemisphere. The drop in global temperatures, however, was nowhere near as significant – somewhere between 0.2°C and 0.6°C from the peak of the Medieval Warm Period (900-1150 AD).] As for the temperature ‘pause’ that occurred between 1998 and 2005, this was really only illusory, as 1998 was an exceptionally hot year. Has it not been so hot, the temperature record would have been broken several times during that seven-year period.  And once the 1998 record was broken, new records have been set regularly over the next two decades – first in 2010, then every couple of years, and now almost every year. By way of comparison, global temperatures rose by an average of 0.07°C each decade after 1880. The most recent decade (2010-19), however, saw an increase of 0.39°C – five and a half times the historical average. The warming trend is clear, and very worrying.  

Temperature data is inaccurate because we don’t have good enough technology to measure the Earth’s surface, the oceans, the stratosphere or the troposphere. So, these cannot be relied on as indicators of global warming. Fact: Temperature measurements are not perfect but provide a very good picture of general trends. These all show significant warming. Interestingly, climate sceptics were happy to use temperature measurements when they thought they showed a fall in global temperatures or, at best, a temperature pause. This was the case in the seven years following 1998, when the temperature record was not broken till 2005. Since then, however, records have been broken repeatedly, so climate sceptics have become hostile to the very idea of measuring global temperatures.  It’s the same with climate models. Sceptics use them when they confirm their own views, but reject them when they don’t.