system
Given the following post, respond as if you're commenting on Reddit:
human
Why is it more difficult to breathe warm air?

When I get into my car when the sun has been baking it all day, I feel like I can barely fill my lungs.  In cool air, though, breathing is much more comfortable.  Why is body-temperature air stifling vs cooler air?
gpt
It’s not harder to breath, but there is less oxygen per volume of hot air compared to cold air. Cold gases are denser, meaning more oxygen per volume, your body feels this lack of oxygen in the air and tells you to breath harder to make sure you continue to get the requisite amount of oxygen that your body needs to survive.