Where has all the blue gone?

Below are a couple shots of last Sunday from my backyard. The deep blue hints at what kind of sky we might have enjoyed. There wasn't one naturally formed cloud in the entire sky. When I first started noticing them in 1997 (before I even heard the term "chemtrails"), I thought they were linear clouds. That's how far they are looking like contrails. Of course it's understandable that younger people don't know any better, but it is strange that people who've been around longer and recognize it as a new phenomenon can accept the prosaic explanation.

Are there any photos like these predating the 1990s? If not, why?