2.3 - The effect of the atmosphere

So interaction of light with objects allows us to see them. But what affects radiation reaching a sensor at the top-of-atmosphere? What is the contribution from the surface? How does radiation interact with the atmosphere?

Exercise: Please look at next figure showing the spectral distribution of the solar radiation both at the top of the atmosphere (TOA) and at ground level. Can you select the proper legend to the figure, from the two options below?

Next figure illustrates what happens to solar radiation in its transmission through the atmosphere:

As you can see, solar radiation is attenuated by:

  • Reflection (by clouds and atmospheric constituents);
  • Absortion (by atmospheric constituents)


What are the atmospheric constituents causing this attenuation of solar radiation? Do they act equally for the all regions of the electromagnetic spectrum?