There is growing evidence that climate change is occurring and having effects. The greenhouse effect caused by mankind (anthropogenic) accounts for about 60–70 % of these effects, while natural processes play a far more limited role. Since the beginning of the Industrial Age, human beings have been emitting greenhouse gases into the atmosphere, primarily as a result of their energyintensive lifestyle. A primary factor has been the burning of fossil fuels, but also non-energetic production  processes contribute to the growing concentration  of greenhouse gases in the atmosphere. The climate change thus induced is already clearly identifiable as a rise in global temperatures.