The green cloud in Las Vegas is definitely bad air, filthy bad for you but some of us have to live there. I moved to Oregon at around 900' above sea level after my pulmonologist said moving to a lower elevation would probably help. I have to travel to Albuquerque once in a while for my job and it is at about 5300' above sea level and I have to use my oxygen constantly at about 2. Here in Oregon with the trees and not many factories, I have great air quality and do not need my oxygen at all. The only thing really bad about here is the fires in the summer and they are hard to take, I usually just hook up the trailer and go for a road trip till the fire is out. Humidity makes it hard for me, in the winter we get a fog and it gets pretty humid and makes it hard to breathe, but when I do go to the East coast where the humidity is high it does put a damper on my breathing, so I think you are just up against the elements wherever you are.

If the air is hot and stuffy it's extremely hard to breathe. Some humidity makes it easier to get a breathe of it's cool. Not cold?

It seems like there is a green ugly smog cloud that hovers over Las Vegas, not sure the air quality is that great, but it is at 2000' above sea level so should probably be ok, but have to remember it is really bad air quality, probably, I am not an expert in that area, would need to ask a meteorologist about their air quality.

Indiana winters are especially hard I can’t catch my breath in the cold

Thank you comparing it to Indiana!