Solar and Infrared Radiation Measurements

11 Net Radiation Measurements

Changes in the atmospheric abundance of greenhouse gases and aerosols, in solar radiation and in land surface properties alter the energy balance of the climate system. These changes are expressed in terms of radiative forcing, which is used to compare how a range of human and natural forces drive warming or cooling influences on global climate.

Intergovernmental Panel on Climate Change (2007)

11.1 Introduction

Net radiation (R_n) is the algebraic sum of the downwelling broadband solar, the same as GHI, also called shortwave (S↓), the downwelling broadband infrared, also called longwave (L↓), the upwelling broadband shortwave (S↑), and the upwelling broadband longwave radiation (L↑), that is,

$$R_n\text{=}S\downarrow -S\uparrow \text{+}L\downarrow -L\downarrow (\mathrm{11.1\; ...}$$