Energy Balance Climate Models

Chapter 4Greenhouse Effect and Climate Feedbacks

4.1 Greenhouse Effect without Feedbacks

In Chapter 3, we examined the vertical distribution of temperatures in the atmosphere for some very simplified atmospheric models.¹ In particular, we made the assumption that the spectral dependence of the absorption of infrared radiation by gases in the atmosphere were “gray,” that is, they had no dependence on wavelength. In this chapter, we consider a more realistic absorption spectrum of the gases in the atmosphere. It will be seen that the details of the spectral dependence of the infrared absorption are important in the perturbation of the radiative balance by changes in the concentration of greenhouse gases (GHGs) such as water vapor, carbon dioxide, ...