A Satellite-Based Sky Luminance Model for the Tropics

Figure 6

Example of the plot of 𝜑(𝑍)/𝜑(0) against 𝑍 for solar zenith angle 60^∘≤𝑍_𝑠≤65^∘ and cloud index 0.7≤𝑛≤0.8. 𝑍 is the zenith angle of the sky subzone.