If the Earth was warming, why did the amount of sea ice in the Antarctic increase rather than decrease between 1979 and 2014?  Fact: It is true that Antarctic sea ice did increase by about 3.5 percent between 1979 and 2014, but it began shrinking again in 2015 and has now reached the lowest level ever recorded. [We don’t have figures for before 1979, as this was when satellite monitoring began.]  One reason for the rise in sea ice levels prior to 2014 is that the winds that blow off the continent increased, carrying more cold air out to sea, where ice forms. Another reason is that increasing meltwater from the Antarctic ice sheets led to an increase in ice formation, as fresh water freezes at a higher temperature (0°C) than salt water (-2°C). Finally, higher temperatures increased the amount of snowfall over both the continent and the surrounding oceans, thereby increasing sea ice cover. [This is because warmer air holds more moisture.]  The problem, however, is not the loss of sea ice in Antarctica but the loss of land ice. Between 2002 and 2025, that loss averaged 135 billion tonnes a year, causing sea levels to rise by 0.4 millimetres per year. The science suggests that the rate of loss is only going to increase as the Earth’s atmosphere heats up. [It takes approximately 360 billion tonnes of ice to produce one millimetre of global sea-level rise.]

Global warming cannot be real because some glaciers increasing in size. Fact: A few glaciers are advancing, but the vast majority of the world’s 200,000 glaciers are shrinking. The reason a few are expanding is that in a few places, warmer winter air can lead to more snowfall (as warmer air holds more moisture), thereby increasing the mass balance of glaciers. [The mass balance is the difference between the total gains and losses of ice over a year.] In most glaciers, the extra snowfall does not add to the glacier’s mass, as it melts quickly. Only in a few places does it get incorporated into the glacier. If global warming continues, however, this process will cease completely, and all glaciers will shrink. Non-polar glaciers are currently losing about 150 billion tonnes of ice each year. [This is more than the entire weight of Mount Everest.] To put that in perspective, it takes approximately 360 billion tonnes of ice to produce one millimetre of global sea-level rise. Frighteningly, in 2019 the Greenland ice sheet lost about 500 billion tonnes of ice. Loss of Greenland’s ice is the major cause of global sea level rise at present. If the entire ice sheet were to melt, sea levels would rise by 7.3 metres. Of course, it would take thousands of years for this to happen.] Shrinking glaciers in the US, 1952-2019 [Source: Our World in Data]

In 2010 there was a fall in global sea levels. How could this have happened if global warming were real? Fact: It’s true that sea levels fell marginally in 2010, but this was because very heavy rain fell over Australia and South America, transferring a significant amount of water from the oceans to these two land masses. It took two years for that water to fully drain back into the sea. Once that had happened, sea levels rose again, and have continued to rise ever since.

If climate change is real, why aren’t sea levels rising by much, and why aren’t those rises happening evenly across the globe?  Fact: Sea levels are not even across the globe. Factors like winds, currents, river discharges, and variations in temperature and gravity make sea levels different in different parts of the world. It’s the same with sea level rises. For example, Sydney harbour has only risen by about 10 cm in the last century – about half the global average of 21 cm since 1880 – but in other places, like Micronesia, the sea level has risen by more the global average.  Worryingly, sea levels are rising at an increasing rate. For the first seven decades of the 20th century, they rose at an average of 1.3 millimetres per year. However, between 2006 and 2018, they rose at 3.7 millimetres per year – an increase of 185 percent.  In fact, we are only in the early stages of sea level rise. Around 400,000 years ago, when global temperatures were about 2°C warmer than the average for the past 8,000 years, sea levels were 6-9 metres higher than they are today. At current rates of warming, we are headed for a rise of up to one metre by the end of the 21st century. Some scientists believe the eventual rise will be as much as 3 metres. [It should be noted that tides are not uniform across the globe either. In some places, there is barely any difference between high tide and low tide at certain times of the year. In other places, such as the Bay of Fundy in Canada, the difference is as much as 16 metres!] One city that is particularly threatened by sea level rise is New York, where levels have risen by 22 millimetres since 1950. The problem is being exacerbated by the fact that the city is sinking – at the rate of 1-2 millimetres a year, with some parts sinking at twice this rate. This is due to some of its skyscrapers having been built on sand and clay rather than solid rock. As a result, the city has faced two recent inundations – one in 2012 and the other in 2021 – when hurricanes caused whole areas to be flooded. These ‘once in a century’ events are now happening with alarming frequency. Other cities facing the threat of inundation include Miami, New Orleans, Shanghai, Jakarta, Bangkok, Lagos and Alexandria.  Global sea level rise, 1880-2020 [Source: Wikimedia Commons]

Scientists came up with the term ‘climate change’ to cover for the fact that the world stopped warming in 1998. Fact: Climate sceptics have this completely the wrong way round. The term ‘climate change’ is actually much older than ‘global warming’ in the scientific literature. It dates back to the 1850s, and refers to “changes in a particular climate variable over a given area.” ‘Global warming’, by contrast, refers to changes in the Earth’s overall temperature. It is just one of various types of climate change. The term was first used in the 1960s but was popularised by Professor Wallace Broecker in a 1975 article in the journal Science.

Climate science is too new a discipline to be taken seriously. It only started in the 1970s. Fact: Climate science is not new at all. In fact, it’s been around for almost 200 years.  The French physicist Joseph Fourier, who developed the Law of Heat Conduction, first postulated the idea of a greenhouse effect in 1824, as a way of explaining why the Earth was not a ball of ice. Something in the atmosphere was trapping infrared radiation, but he did not know what. Another French physicist, Claude Pouillet, demonstrated that some infrared radiation was not returning to space. In 1838 he speculated that this might be because it was being trapped by CO2 and water vapour.  Then, in 1856 the American scientist Eunice Foote demonstrated that CO2 was responsible for trapping heat in the atmosphere. Six years later, the Irish physicist John Tyndall reached the same conclusion, adding that methane was also a greenhouse gas. In 1896, the Swedish physical chemist Svante Arrhenius concluded that human activity was heating up the planet. Ten years later he calculated that a doubling of CO2 would result in a 4°C increase in global surface temperatures – a figure that is very close to modern day predictions. [Arrhenius won the Nobel Prize for Chemistry in 1903.] Finally, in the 1930s the English meteorologist Guy Stewart Callendar gathered global CO2 and temperature measurements from around the world over a 50-year period and demonstrated that both were rising, and that the likely cause of the latter was the increase in the former. His experiments suggested that at least half of the temperature rise to that point was attributable to human activity. This was the first time anyone had suggested that humans were causing global warming. Callendar calculated that a further temperature increase of 2°C might act as a ‘tipping point’ for increases that would be irreversible. [It was another 40 years before scientists had the instruments needed to prove Callendar right.] Hence, climate science is not a recent development. It has been a part of modern science for as long as Darwin’s theory of evolution and longer than Einstein’s theory of relativity. Swedish physicist Svante Arrhenius [Source: PICRYL]

Governments and research institutions are faking temperature measurements, to make it look like the Earth is warming.  Fact: This claim is completely ludicrous, as it implies that the US government is part of a conspiracy, even with President Trump declaring that global warming is a hoax. If it really were easy for governments to cover up the truth, you would expect the US to have planted weapons of mass destruction in Iraq, to justify the 2003 invasion. Instead, it sent 1,500 weapons inspectors to scour the country for WMD, then admitted that no such stockpiles existed. Conspiracy theories are almost never true, particularly in countries where the government is held accountable by voters and the media. [In authoritarian regimes, by contrast, it is a different matter, as the government controls all the levers of power. Even so, the truth still has a way of getting out over time.]

Scientists can’t explain everything about the climate, so we should wait until they can before taking any action.  Fact: Again, this argument is ridiculous. It’s like saying, “Scientists don’t know everything about cancer, so we shouldn’t tell people to stop smoking until they do,” or “We don’t know everything about space, so we shouldn’t launch spaceships until we do.”

In 2005, Professor Tim Flannery said that drought conditions would become permanent in eastern Australia and that “the rain that comes won’t fill our dams”? Neither of these things have happened, so how can anything climate scientists say be taken seriously? Fact: It’s true that Tim Flannery did say those things, and they have not proved to be correct – thus far, at least. The fact is, Tim Flannery is not a climate scientist; he’s a palaeontologist. So, his words do not discredit climate science, any more than would the words of a psychologist or a dermatologist on the same subject. It is unfortunate that he later became the head of the Climate Commission, so was seen as the public face of the climate movement in Australia. While he has been a tireless advocate for climate action in this country, he did not do the movement any favours by saying what he did. Even so, there is good reason to be concerned about the availability and distribution of water in Australia. It’s now becoming clear that climate change is resulting in more droughts and greater flooding. The problem is, it’s proving hard to predict where each of these will occur. What we do know is that neither will be good for the environment or the economy.

Back in the 1970s, scientists predicted that the Earth was going to cool, not warm. That did not happen, so we can’t take scientific predictions about global warming seriously. Fact: Scientists did not predict that the Earth would cool. What happened was that researchers at NASA calculated what would happen if there were a quadrupling of particulate matter in the atmosphere. They predicted that this would block enough sunlight to reduce global temperatures by 3.5°C and trigger another ice age. Of course, this scenario did not occur, as governments introduced legislation in the 1970s to clean up polluting industries. The reason the public became aware of the story was that Time and Newsweek magazines published articles at the time about the possibility of an imminent ice age. Scientists were not wrong in their predictions, as they never made such predictions. This was just a media ‘beat-up’.