It is appropriate to think of the discipline of atmospheric radiation as one of the building block subjects of the atmospheric sciences linking the fields of chemistry, aerosol and cloud physics, thermodynamics to global climate and climate change. A convenient way to think of the research of this discipline is to consider it divided into two broad but not necessarily distinct categories---one that seeks to understand how the interactions between radiation and the atmosphere determine the distribution of radiant energy on all scales and a second that attempts to exploit such an understanding, mostly as they apply on the smaller scale, to form the basis for most of the remote sensing methods currently used to observe the atmosphere. The first line of enquiry provides the fundamental understanding of the radiative forcing of climate, for example, and significant advances in our understanding of this forcing have emerged over the last few years. Perhaps even more activity has been invested in the second area of research especially with the emerging era of the Earth Observing System (EOS) [e.g., King et al., 1992]. Remote sensing has also become a tool in climate research over the last few years with the application of satellite data in studies of fundamental climate processes.
It is clearly not possible to review both research areas of atmospheric radiation in detail so only a limited amount of the remote sensing research is described below. It is primarily only the research in remote sensing that has been applied specifically to contribute to our basic understanding of radiative processes that is discussed here.