Yep, 'chemtrails' are just another conspiracy theory, popularised by the ability of any uninformed person being able to publish any old crackpot idea on the Internet. Don't be fooled by it! Put it in a box beside moon landing conspiracies, climate denial, 9-11 troofers, HAARP, Obamas birth certificate, and various other unsupported conspiracy theories. The clouds you've pictured are just a mix of regular cirrus and normal aircraft contrails. There are more contrails than 40 years ago (much more air traffic), but there's nothing sinister in that, and I've rarely seen weather conditions in Australia where contrails have significantly affected sky quality. I saw this more often near popular flight paths in the UK under cold high pressure systems in winter - sky criscrossed by normal contrails that lasted longer because atmospheric conditions were right.
You don't hear about the ozone layer so much because thanks to the Montreal Protocol, we have cut our emissions of CFCs, and so the hole is not growing now, and is beginning to shrink as some of the CFCs come out of the atmosphere - given the residence time of the molecules, this takes decades. Problem identified by science (a 1985 Nature paper) ... action ... solution. The same happened with Y2K, we took action to solve the identified problem, and now you don't hear so much about it.
Clear skies
