At Humanist Climate Action, we believe there are powerful interests that want to discredit or dismiss the overwhelming evidence on climate change. But the scientific community has methods of verifying scientific research and assertions. Research papers are ‘peer-reviewed’, and through this method, and other checks, a consensus is arrived at about what science is sound and valid. 97-99% of climate scientists consider climate change, and the predictions on how it will accelerate if left unchecked, are beyond doubt.
Social media means that all sorts of versions of reality can be easily circulated, and millions of people are choosing to believe ideas with no scientific proof, or not coming from a source that checks or verifies it’s information. Below are examples of disinformation about climate change, and the evidence and science needed to challenge them.
Climate change is not caused by the actions of humans
Natural influences have always created variability in the Earth’s climate but the warming of the last 60 year is far outside the range of long-term climate variability estimated by pre-instrumental data and simulated climate models. According to the Intergovernmental Panel on Climate Change (IPCC), the leading international body for science related to climate change, it is virtually certain that the Earth’s warming since at least 1951 cannot be explained by natural influences, such as solar irradiance and volcanic aerosols, alone. It is extremely likely that human influences, and in particular the release of greenhouse gases into the Earth’s atmosphere, have accounted for more than half the increase in average global surface temperatures between 1950 and 2010.
Atmospheric CO2 reached 407 parts per million in 2018, its highest level for at least 800,000 years, exacerbating the Earth’s natural greenhouse effect. According to satellite data, solar output has decreased since the 1970s, and yet, during that time, the Earth has continued to warm’
There is no scientific consensus on climate change
According to a November 2019 study, 100% of active research scientists agree on the existence of anthropogenic global warming. The majority of leading scientific organisations worldwide also support this position, including the World Meteorological Organization, the World Health Organization, the International Science Union (formerly the International Council for Science), and all national science academies of the G8+5 states.
Extreme weather is not caused by climate change
According to the IPCC changes in extreme weather have taken place since the middle of the 20th century. As of 2019, of the 230 peer-reviewed studies examining the link between climate change and specific extreme weather events including heatwaves, droughts, and heavy rainfall, 68% found a relationship. Almost all studies on heat events suggested the influence of anthropogenic climate change. It is likely that the frequency of heatwaves has already increased across Europe, Asia, and Australia, and anthropogenic climate change is thought to have doubled their frequency in some regions. Climate change influences the probability of extreme weather in a variety of ways. Warmer air can store more water, resulting in heavier rainfall and flooding. By increasing evaporation from the soil, rising temperatures also increase the severity of droughts.
We are coming out of a ’little ice age’ anyway
The ‘little ice age’, a period of cooling between the 16th and 19th centuries, is often used to suggest that recent trends reflect an only cyclical recovery from colder climatic conditions. But cooling trends over this period do not compare to either the scale or magnitude of contemporary climate change. To call the period an ‘ice age’ is a misnomer – based on climate reconstructions, temperatures fell only by an average of 0.5°C, compared with consistent warming of about 1°C since the beginning of the industrial revolution and an average increase of 0.13°C for every decade of the last 50 years. The little ice age was confined largely to the northern hemisphere and present climate change is a global phenomenon. Although the little ice age can be explained by natural variation, global warming cannot.
Climate change is part of the Earth’s natural cycle
The climate has fluctuated between periods of colder and warmer conditions but the current rate of warming is anomalous. After the last ice age, it took 10,000 years for global temperatures to rise between 3°C and 8°C, compared with a rise of 1°C in just over a century. No natural phenomenon, whether solar output, oceanic circulation or volcanic eruptions, has been found to explain the magnitude of the present warming. The release of greenhouse gases into the atmosphere by humans is the only explanation.
Increasing the average temperature by a couple of degrees is not harmful
A mean global surface temperature rise of 2°C against pre-industrial levels, which is higher than the maximum committed to by the signatories of the 2015 Paris Agreement, will threaten biodiversity, human health, and food production, among much else. For every degree of temperature rise, global crop yields are likely to fall between 3% and 7% depending on the crop, with implications for global food security. With only a 2°C rise the geographic range of insects is likely to fall by 18%, of plants by 16%, and of vertebrates by 8%. Given an increase of 2°C, almost 40% of the world’s human population will probably be exposed to severe heat waves at least once every five years. Restricting warming to 1.5°C will have better outcomes, but we will still have to adapt to extensive changes in our environment. An increase in heat waves, cold events, heavy rain and droughts have already been observed around the world since the start of the 20th century, and Arctic ice is 65% thinner than it was in 1975. Rising temperatures will lead to the melting of permafrost and glaciers, causing the release of carbon dioxide and methane into the atmosphere. Rather than storing carbon, permafrost could become a significant source of planet-heating emissions, and this in turn could cause a negative feedback loop. When the ice in permafrost melts, the ground becomes unstable and can slump, causing rock and landslides, floods, and coastal erosion. People and animals and their diseases have been frozen in the permafrost for hundreds of years, but bacteria and viruses can survive in permafrost for hundreds of thousands of years – thawing may release these bacteria into the environment.
We cannot prevent climate change
When nations work together through international cooperation we have a good track record on managing environmental degradation, such as repairing the hole in the Ozone layer. Although the Earth would be expected to warm by another 0.6°C between by 2100 even if atmospheric greenhouse gases were held at present levels it is possible to prevent more warming and avoid some of the worst effects of climate change. Limiting the rise to 1.5°C above pre-industrial averages would limit the severity of heatwaves, water insecurity and sea-level rise. Changes in our personal lives such as reducing consumption and changing transport methods are important but a globally-coordinated, amplified response is necessary to tackle such a complex problem transcending international borders. This will need to be accompanied by adaptation, including learning to live with the changes caused by climate change. We certainly won’t succeed if we don’t even try.
Climate change is about raising taxes
The belief that climate change is a front for raising taxes is worryingly prevalent, though evidence to support it is scant. Less than 6% of global greenhouse gas emissions are taxed at present, but where carbon taxation does exist, it has had a proven influence on emissions. The UK’s carbon price support mechanism helped to reduce coal generation by 73% between 2013 and 2017. If climate change is left unchecked the cost of failing to act will be far higher than any present ‘climate tax’. According to the Stern Review, it could cause the loss of more than 5% of global GDP every year, rising to 20% when secondary impacts are considered. Complying with the 2015 Paris Agreement could bring a global gain of more than US$17 trillion a year by 2100, compared with allowing the Earth to stay on track for a warming of 4°C.