Dland10

So I have noticed that my windshield has like, ripples or waves on it. I just got the car not too long ago and have been away from home for several months and just noticed it. And it's only on the bottom half of the windshield, and sort of makes things blurry. I thought it could be old wax or something, but windex wont even bring it out, just makes it super clean and therefore more noticeable. Im not sure if this is a common thing or if anybody has heard of it, or even what it is. But I don't like it...