The lecture was filmed in October 2013 when it was given as the KIT Climate Lecture. Short abstract: In his talk Prof. Haug explains the influence of man-made changes such as greenhouse gas emission to the carbon cycle. He also describes the consequences of global warming like sea level rise or the shifting of climate zones. Prof. Haug further illustrates how analyzing drilling cores contributes to the investigation of cold and warm periods in the past. To slow down the recent man-made climate change it would be necessary to uncouple emissions from a rising world population. Prof. Haug reckons that energy efficiency and the use of renewable energies are key technologies for this.