The global climate system is determined by the atmosphere, the hydrosphere, the lithosphere and the biosphere, and is extremely complex with a lot of non-linear connections, the understanding of which requires system-thinking. In spite of that, climate policy in most cases deals solely with the atmospheric concentrations of greenhouse gases, although alteration of biogeochemical cycles through excessive use of natural resources and decrease of natural surface cover due to degradation of ecosystems are, though very hard to tackle, just as determining causes of climate change.