Electromagnetic Scintillation describes the phase and amplitude fluctuations imposed on signals that travel through the atmosphere. These volumes provide a modern reference and comprehensive tutorial for this subject, treating both optical and microwave propagation. Measurements and predictions are integrated at each step of the development. The first volume dealt with phase and angle-of-arrival measurement errors, which are accurately described by geometrical optics. This second volume concentrates on amplitude and intensity fluctuations of the received signal.