ABSTRACT
This chapter focuses on the output dimension: climate change. Intergovernmental Panel on Climate Change has agreed on six gases which, through intensified anthropogenic use and release, are responsible for accelerated climate change: carbon dioxide, methane, nitrous oxide, hydrofluorocarbons, perfluorocarbons, and sulfur hexafluoride. The global climate evolves over time owing to naturally occurring factors outside the climate system such as volcanic eruptions and solar variations. Direct emission of water vapor by human activities makes a negligible contribution to climate change, it does not result in a significant change in the balance of incoming and outgoing energy in the Earth–atmosphere system. Although there is empirical evidence for natural climate variability, such climatic changes in the past were nearly independent of variations in the concentration of greenhouse gases. The natural environment has already experienced significant changes as a result of climate change.
