Why does cold air seem to optically zoom in far-away objects?

[Fanny Viksten]

I have noticed that cold air makes far away objects, such as mountains, appear closer than they do in warm clear weather. Does anyone have an explanation for this?

 

[A.T.]

...appear closer ...

How exactly? Taller? Or clearer?

 

[Fanny Viksten]

How exactly? Taller? Or clearer?

They appear larger than when the air is warm. I already stated comparison to a CLEAR warm day, as heat can make the air hazy and of course that would affect their visibility.

 

[CWatters]

Try taking photos to compare?

 

[A.T.]

They appear larger than when the air is warm. I already stated comparison to a CLEAR warm day, as heat can make the air hazy and of course that would affect their visibility.

A temperature gradient can act like a lens, and make objects seem taller.