Paul Joe has some questions for you that might help deal with the AP issue ...
- Can sub and super - refraction happen at the same time?
- Here are two scenarios, what are the implications?
- It is possible that the top of the beam is sub-refracting and the bottom of the beam is super-refracting? Or is it? Draw a picture.. What is the implication of this? Is the opposite also possible?
- It is possible that the center of the beam is sub/super - refracting as it propagates along. What are the implications of this?