What are the causes of climate change? What measures, if any, are needed to combat it? These questions have been hotly debated for years. In an article, Swiss television weather forecasters have now concluded that the central arguments of so-called ‘climate sceptics’ are all false. We have taken a closer look at these arguments.

Below, we list the statements made by ‘climate sceptics’ that the SRF authors have taken up, how they claim to have refuted them (under the heading ‘state of science’), and what to make of them.

Statement 1: The measured warming is incorrect. For example, because thermometers used to be located in the countryside and are now located in a (warmer) city.

State of science: A wide variety of measurement methods clearly show the warming trend worldwide. These include thermometers, satellites, measurements from ice cores, and weather balloons.

Comment: Few people question that the Earth has become warmer. Therefore, this is hardly a central statement of the ‘climate sceptics’. However, there are repeated doubts as to whether the urbanization effect is adequately taken into account in temperature measurements (i.e., the effect that temperatures are not rising due to climate change, but only appear to be rising due to the increasingly urban environment of measuring stations). However, SRF Meteo does not address this at all.

Statement 2: There is no scientific consensus. Even experts doubt climate change.

State of science: 97 percent of climate scientists believe climate change is real and see humans as the cause.

Comment: It is true that most leading climate scientists are convinced that global warming is man-made. The 97 percent argument is based on an evaluation by Australian cognitive scientist John Cook in 2013, who examined 12,000 scientific studies on climate change. However, he discarded 66 percent of these publications because they did not contain any statements about human influence. Of the remaining studies, 97 percent indicated that the authors considered humans to be at least partly responsible for global warming. However, many ‘climate sceptics’ do not question that humans are partly responsible for climate change, but only that they are solely to blame. In addition, James Cook’s survey also showed that two-thirds of climate researchers have not made up their minds about human influence.

Statement 3: The climate has always changed. There have been periods in Earth’s history when it was warmer than today.

Scientific consensus: The climate has always changed. However, the current warming is unprecedented in the last 2000 years. The Earth can exist at much higher temperatures, but human civilization cannot necessarily do so.

Comment: SRF Meteo bases its statement on findings by the Intergovernmental Panel on Climate Change (IPCC), which describes the current warming as unprecedented in the last 2000 years. However, there are considerable doubts about this. On the one hand, the statistical methods used to produce the IPCC’s ‘hockey stick’ curve have already been exposed as scientifically untenable. On the other hand, we know from the Roman temperature optimum (approx. 2000 years ago) and the Medieval temperature optimum (approx. 1000 years ago) that glaciers retreated further then than they have today. Given the lack of measurements, it is impossible to say with certainty how high temperatures were at that time. In any case, human civilization will not simply disappear even if it gets much warmer.

Statement 4: It’s the sun. Sunspots or solar activity are causing global warming.

Current scientific understanding: Solar radiation is indeed not constant, but even in periods when the sun was weaker than usual, the Earth became warmer.

Comment: Here, too, SRF Meteo relies on the Intergovernmental Panel on Climate Change, which supports this view. However, there are serious scientists such as Nir Shaviv from the Hebrew University of Jerusalem who give greater weight to the influence of the sun. The IPCC consistently ignores such voices.

Statement 5: Climate change has positive effects. Better conditions for agriculture or fewer deaths from cold weather.

Scientific consensus: There are some possible positive effects of climate change. However, the risks far outweigh the benefits.

Comment: Global warming undoubtedly has many positive consequences. SRF Meteo bases its claim that the risks far outweigh the benefits on the Intergovernmental Panel on Climate Change. The fact is that the positive effects of climate change are hardly ever mentioned in the media. This leads to a distorted public perception of global warming.

Statement 6: The weather has always been extreme. There have always been floods and droughts.

Scientific consensus: True. However, many extreme weather events have become more frequent and intense due to climate change, such as heat waves, droughts, and heavy rainfall.

Comment: For once, SRF Meteo is not relying on the IPCC for this statement. This is because its latest Assessment Report contains a table showing that there is no global trend towards more frequent or more severe floods, storms, droughts, or heavy rainfall. In this respect, SRF Meteo is wrong – except when it comes to heat waves. However, it is a truism that these are becoming more frequent as temperatures tend to rise.

Statement 7: Climate models are poor. The models were created to fit the past and say nothing about the future.

State of science: A climate model is based on the laws of physics. That is the only reason it can accurately reflect the past. The laws of physics will remain valid in the future.

Comment: Physical laws apply without restriction. However, it is sometimes difficult to determine exactly what these laws are. Climate science certainly has its work cut out in identifying them, because the chemical and physical interactions in the atmosphere are extremely complex. A few years ago, even leading IPCC researchers had to admit that the climate models used were failing because they could not accurately represent not only the future but also the past. In this respect, the reality is even worse: the models used by the IPCC often do not even fit past times.

Statement 8: Weather forecasts are wrong, so climate projections are too. It is impossible to forecast the weather for the week after next, so why should a climate projection for a hundred years work?

State of science: These are completely different questions. For a weather forecast, you need to know the exact state of the atmosphere. A climate projection only needs to be able to simulate climatic conditions realistically. Weather chaos is eliminated in a climate model by long-term averages.

Comment: Of course, climate and weather are not the same thing. Nevertheless, it seems hubristic when leading scientists suggest that climate developments can be predicted with pinpoint accuracy for many decades or even centuries into the future. The idea that the future global temperature can be set to within a tenth of a degree, as if with a thermostat, is even more absurd.

Statement 9: Climate protection is bad for the economy. We need fossil fuels for further economic growth.

State of science: The costs of inaction are most likely greater than the costs of mitigating climate change.

Comment: Anyone with a modicum of common sense can easily see that it will be impossible to replace fossil fuels in just a few decades. Consequently, people would have to be deprived of energy in order to achieve climate targets. This would lead to economic collapse and crop failures. The result would be poverty, hunger, and death. The alleged calculations of so-called climate economists, according to which climate protection is worthwhile on balance, are politically motivated wishful thinking.

Statement 10: Renewable energies are unreliable. On cloudy days, there is hardly any solar energy, and on sunny days, there is too much.

State of the technology: There are fluctuations in renewable energy production. However, this is not the case for all types, such as hydropower or geothermal energy. Solutions are being worked on to address the fluctuations, such as smart grids or storage technologies.

Comment: At SRF Meteo, they know full well that the transition of the energy system is primarily about solar and wind power and, at most, marginally about electricity from geothermal and hydropower. And with wind and solar power, the weather dependency of production is undeniably the central problem that makes these forms of energy virtually unusable. By saying that “solutions are being worked on”, SRF Meteo admits that these solutions for fluctuating energy production do not exist right now.