PARALLAX

• Parallax refers to the displacement of cloud locations due to increasing viewing angle.  Here is an illustration.
• Parallax is a function of:
  • The viewing angle
  • cloud height
• The offset is away from the satellite along a great circle arc.

• Here are examples of the parallax-induced cloud displacement for GOES and Polar orbiting satellites as a function of angular distance from nadir.
• Notice that the parallax-induced cloud displacement gets real bad at angles greater than 60° for the GOES imagery.
• Parallax also applies to terrain features such as mountains.