Since the Industrial Revolution, and in particular in the twentieth century, energy consumption, agricultural activities and deforestation have increased and are still increasing dramatically. These human activities are changing the climate system on a global scale and for the first time in the history of Planet Earth we face the risk of human induced climate change. The working of and the human influence on the climate system will be explained. These models and their limitations will be discussed and the results of climate projections for the next century will be shown.
Climate always varies, even without human influence.
The important role of this UN Panel on the edge between science and policy making will be discussed.