The science of climate change is over 150 years old and is perhaps the most tested part of modern science. But the energy industry, political lobbyists and people with vested interests have spent the last 30 years sowing baseless doubt about this science.
The latest estimate reveals that the world’s five largest publicly owned oil and gas companies spend approximately US$200 million annually on lobbying to control, delay or block binding climate-motivated policy.
This systematized and orchestrated climate change science denial has majorly contributed to the lack of progress in reducing global greenhouse gas (GHG) emissions to such an extent that we are facing a global climate emergency. But when climate change deniers cite certain myths that are at best fake news and at worse straight lies to challenge the science of climate change, ordinary people might find it difficult to see through the false narrative.
Five commonly used myths and the real science that debunks them are described below.
- Climate Change Is Just Part Of The Natural Cycle
The climate of the Earth has continuously been changing, but the study of palaeoclimatology or “past climates” shows us that the changes happening in the last 150 years i.e. since the start of the industrial revolution, have been extraordinary and cannot be natural. Modeling results submit that future predicted warming could be unprecedented compared to the previous 5 million years.
The “natural changes” argument is accompanied with the story that the Earth’s climate is simply recovering from the cooler temperatures of the Little Ice Age viz. 1300-1850AD and that temperatures today are actually the same as the Medieval Warm Period of 900–1300AD. The problem with this theory is that the Little Ice Age and the Medieval Warming period were both not global but regional changes in climate affecting north-west Europe, eastern America, Greenland, and Iceland.
A study covering 700 climate records showed that, over the last 2,000 years, the only time span when the climate all around the world has changed at the same time and in the same direction has been in the past 150 years, when over 98% of the surface of our planet has warmed.
- Changes Are Due To Sunspots/Galactic Cosmic Rays
Sunspots are storms on the surface of the Sun that include intense magnetic activity and can be accompanied by solar flares. These sunspots do possess the power to modify the climate on Earth. But then again scientists using sensors on satellites have been measuring the amount of the sun’s energy hitting Earth since 1978 and there has been no rising trend. So these solar phenomena cannot be the cause of recent global warming.
Galactic cosmic rays or GCRs are high-energy radiations that originate outside our solar system, maybe even be from distant galaxies. It has been proposed that they may help to seed or “make” clouds. So reduced GCRs striking the Earth would mean fewer clouds, which would reflect lesser sunlight back into space and thus cause Earth to warm.
But there are two apparent problems with this concept. First, scientific evidence displays that GCRs are not very effective at seeding clouds. And second, during the last 50 years, the amount of GCRs have essentially increased, hitting record levels in recent years. If this idea were right, GCRs should be cooling the Earth, but that is not the case.
- CO2 Is A Small Part Of The Atmosphere So It Can’t Have A Large Heating Effect
This supposed common-sense scale argument is completely wrong. In 1856, American scientist Eunice Newton Foote carried out an experiment with an air pump, two glass cylinders, and four thermometers. It demonstrated that a cylinder containing carbon dioxide that was placed in the sun trapped more heat and stayed warmer longer than a cylinder with normal air.
Scientists have recreated these experiments in the laboratory and in the atmosphere to demonstrate again and again the greenhouse effect of carbon dioxide.
The “common sense” angle that a very small part of this gas can’t have much of an effect on Earth is easily shot down by the fact that it only takes 0.1 grams of cyanide to kill an adult, which is around 0.0001 percent of your body weight. Compare this with carbon dioxide, which currently comprises 0.04 percent of the atmosphere and is a strong greenhouse gas. Meanwhile, nitrogen constitutes 78 % of the atmosphere and yet is highly unreactive.
- Scientists Manipulate All Data Sets To Show A Warming Trend
This untrue accusation is used to attack the credibility of climate scientists. It would require a grand conspiracy covering thousands of scientists in more than 100 countries to reach the scale required to execute this.
Scientists frequently correct and validate the data. For instance, historic temperature records may need correction as the way they were measured has changed. Between 1856 and 1941, most sea temperatures were recorded using seawater hoisted on deck in a bucket. But this was not consistent as there was a swing from wooden to canvas buckets and from sailing ships to steamships, which consequently altered the height of the ship’s deck. All these changes in turn altered the amount of cooling caused by evaporation as the measuring bucket was hoisted onto the deck. Since 1941, most measurements are made at the ship’s engine water intakes, so there’s no cooling from evaporation that needs to be accounted for.
Again, many towns and cities have expanded and so the old meteorological stations that were first in rural areas are now in urban areas which are typically significantly warmer than the surrounding countryside.
If such changes to the original measurements are not made, then Earth’s warming over the last 150 years would have seemed to be even greater than the change that has actually been observed, which is now about 1˚C of global warming.
- Climate Models Are Unreliable And Too Sensitive To Carbon Dioxide
This stand is also incorrect as it deliberately misunderstands how models work to downplay the seriousness of future climate change. There is a wide range of climate models, from those meant for specific studies like the understanding of clouds to all-purpose circulation models (GCMs) that are used to predict the future climate of our planet.
There are more than 20 major international centers where teams of some of the smartest people in the world have constructed and run GCMs containing millions of lines of code to represent the very latest understanding of the climate system. These scientific models are continually tested against historic and palaeoclimate data as well as individual climate events like large volcanic eruptions to ensure they reconstruct the climate as accurately as possible.
A single model is never considered correct as they represent a very complex global climate system. But with so many different models built and calibrated independently implies a certain level of confidence when the models agree.
Considering that the whole range of climate models submit that a doubling of carbon dioxide could warm the planet by 2˚C to 4.5˚C, with an average of 3.1˚C. All the models also show a significant amount of warming when extra carbon dioxide is supplemented to the atmosphere. The scale of the predicted warming has remained very similar over the last 30 years in spite of the huge increase in the complexity of the models, showing it is a robust outcome of the science.
By combining all our scientific knowledge of natural phenomena linked to solar, volcanic, aerosols and ozone in addition to man-made greenhouse gases and land-use changes, factors warming and cooling the climate reveals that 100% of the warming observed over the last 150 years is caused by humans.
There is absolutely no scientific support for the continual denial of climate change. The Intergovernmental Panel on Climate Change aka IPCC established by the United Nations to openly and transparently summarizes the science of climate change delivers six clear lines of evidence for this reality.
As extreme weather is becoming more and more common, people no longer need scientists to tell them that the climate is changing as they can experience it firsthand.