7 – Climate change

The current states of important climate parameters are illustrated here with a focus on the troposphere from an atmospheric chemical modeling perspective. Observed climate changes are described for periods prior to and after 1850. To analyze signals of climate change, the concept of radiative force is explained. Then, anthropogenic perturbations to the climate system are discussed using radiative forces of greenhouse gases, such as CO 2 , CH 4 , N 2 O, chlorofluorocarbons (CFCs), O 3 , and aerosols. Climate modeling results are interpreted to understand important processes that regulate climate changes due to human activities. Further improvements on climate simulations are identified.