Popping of the ears

From my understanding your ears pop due to a change in atmospheric pressure. Its a reaction of your body to equalize the pressure in your ear drums to the outside pressure. As atmosphere pressure increases it creates like an air pocket inside your ears and you should notice that just before your ear pops your hearing will be poor. The popping noise itself is due to the air bubble releasing/"popping" out of the ear.

I think it could be due to pressure the builds up or infection even in some cases but it's always good to get them checked out by a doctor. I know sometimes when I blow my nose and it is stuffy my ears do tend to pop. So I figure it is caused by the pressure built up in them and with me blowing hard it's gotta go somewhere.