random question

My living room windows face south; therefore my apartment gets a lot of light. This is a valuable asset when living in Manhattan, and I am thankful for it. Also, as a norm for this city, I have radiant heat, and there is a radiator stationed under one of the windows in my living room.

I was sitting still thinking (or in a cold medication stupor, you choose) when I noticed the bright panes of light on the floor were being distorted by the waves of heat coming off the radiator. But when I look out the window nothing in my line of vision is distorted. I look back at the floor, the light still looks as if smoke is rising past my window, but when I look back out my view is clear as day.

What is up with that?

In movies there is often that scene where the characters are caught in the desert and the scenery is altered and maligned from the heat, sizzling and moving. So I get that it probably takes a significant area emitting heat (such as a desert compared to a radiator) to affect our vision. But then why is a small area emitting heat visible to us at all, via light reflection? I mean, sight is sight, it all comes down to what our brains can process, right? Why can my same eyes perceive the same phenomena occurring only on the floor and not through the glass?

Ohhhh, the mystery.

For all you schlubs who don't have a radiator under a brightly lit window, next time you are driving into sunlight on a cold and very sunny day turn all the heat onto the windshield and you will see the same effect on your dashboard. You too can share in the wonder.

And yes, I did just spend a half hour of my life looking back and forth between the floor and the window. Get over it.