Anyone who talks about the causes of climate change cannot avoid one central concept: the greenhouse effect. This effect owes its name to the comparison of the earth with a garden greenhouse. Put simply: just as glass keeps the heat in the greenhouse, the greenhouse gases in the atmosphere keep the heat on earth. Greenhouse gases include carbon dioxide (CO₂), methane and nitrous oxide. They hold back some of the sun’s rays reflected back from the earth and thus contribute to the warming of the planet.
Without the natural greenhouse effect, it would be freezing cold on earth – researchers estimate that the average temperature would be -18 degrees Celsius, today it is +15 degrees Celsius. The problem: In addition to the natural greenhouse effect, there is also the man-made greenhouse effect. The most important cause of this human-created effect is the burning of fossil fuels such as coal or oil, releasing large quantities of CO₂. The CO₂ content of the atmosphere is constantly reaching new highs – and consequently the greenhouse effect is intensifying accordingly. The concentration of other greenhouse gases such as methane and nitrous oxide has also increased significantly – mainly due to the expansion of agriculture.
As a result, the average global temperature has already risen by more than 1 degree Celsius since the beginning of industrialization. Well-known climate researchers agree that this increase is due to humans. “There can never be absolute certainty – but the probability that humans are responsible for global warming is extremely high, close to 100 percent,” said Prof. Mojib Latif from the GEOMAR Helmholtz Center for Ocean Research in Kiel, for example, in an interview.
Prof. Ottmar Edenhofer, Director of the Potsdam Institute for Climate Impact Research and member of the independent Volkswagen Sustainability Advisory Board, expressed similar views. He said: “Today it is one of the best scientifically proven findings that mankind bears a decisive responsibility for the rise in global mean temperatures and climate change through the burning of oil and gas and through deforestation.” The speed of change is unique in the history of mankind.
Statistics show, June 2019 was the world’s hottest month since temperature records began in 1880. In Europe, June was more than two degrees above average. And: since 1950, the global average temperature has already risen by 1.32 degrees Celsius. Since 1850 it has risen by as much as 1.53 degrees Celsius.