Other than knowing which direction is east and which direction is west, or observing for a sufficient timespan (to determine the direction of motion), is there any way of telling whether what one is seeing is a sunset or a sunrise? A priori it seems not but I was wondering if there are some subtler effects beyond Rayleigh.
Note. I just came across an article that mentions that the green flash can occur only at sunset, and provides additional references:
Broer, Henk W. Near-horizon celestial phenomena, a study in geometric optics. Acta Appl. Math. 137 (2015), 17–39.