With the days becoming shorter and shorter, the people over at Vox started noticing that the sunsets at their office in Washington DC were becoming more beautiful. This made them beg the question: Is it possible that late fall and winter sunsets are just … better?
As it turns out, sunsets are, in fact, better during the colder months of the year, according to NOAA meteorologist Stephen Corfidi. Corfidi says peak sunset season for the middle latitudes (think the Northeastern United States) is November through February, and it has to do with the confluence of a few meteorological factors.
Sunset colors are created by a phenomenon called Rayleigh scattering. It’s the same phenomenon that makes the sky appear blue during the day. Sunlight contains all the colors of the rainbow. But not all the colors reach the ground in the same concentration. Nitrogen and oxygen molecules in our atmosphere act as little mirrors for blue and violet light, in particular. That means not as much blue or violet light reaches the ground. Instead, it bounces around in our atmosphere, creating the blue dome of sky we’re all so familiar with.
At sunset, light has to travel through a greater distance of atmosphere to reach our eyes — so even more blue light, and even some green and yellow light, gets filtered out. That leaves us with the warmer hues of the visible light, the reds and oranges, and it’s why many sunsets look like fire.
The air is typically filled with these tiny particles called aerosols, which are produced by things like trees but also by industrial activities. Aerosols attract water vapor and enlarge, essentially filtering the light we see in the sky and scattering it. But in the winter when the air is colder and dryer, there are less of these color-filtering aerosols in the air, meaning we see colors in all their intensity. That’s why the skies above Arctic tend to be so incredible at sunset—in the clean air of the Arctic where there are no trees or industrial activities, aerosols are not present to dampen the intensity of the sunset.
If you’re looking for a more detailed meteorological explanation as to why winter sunsets are so beautiful, take a look right here.