Here is a guest photo from my son. When we came home and reviewed the photos, I thought the camera had malfunctioned (and in a good way). I thought, wow, now I have a camera that will shoot an impressionistic Monet painting. I tried again and again but couldn't reproduce the effect and was stumped. Then I was looking at photos from another local photographer who visited Keeneland on the day after we did and noticed that his wife had a photo that was similar, though not so dramatic. We have both decided that the effect was most likely heat waves coming off the poly track surface. Keeneland doesn't have dirt, the surface is some sort of synthetic 'dirt'.
I thought the old Panasonic digicam had turned into an electronic paint brush but no luck. Here's a link to Sandy's photo, on Flickr which I think is much better because the waviness is less pronounced.