It’s always nice to see a stunning sunset over the horizon and observe its natural beauty. However, most of the sunsets you see today are actually caused by pollution. How are sunsets created this way and why?

The colors in a sunset are the result of sunlight interacting with molecules in the air, specifically nitrogen and oxygen. The sunlight is reflected in all directions in a phenomenon called Rayleigh scattering. This accounts mainly for the prominent blue and violet colors in the sky since blue light is slightly more efficient in absorbing light compared to red. In this phenomenon, all the wavelengths in the sky are scattered, but not equally. 

During the day, the sun shines directly overhead. Light only travels a short distance through a relatively thinner section in our atmosphere. As the sun edges towards the horizon near the end of the day, light travels a longer distance and is scattered by air molecules. By the time it reaches the naked eye, most of the blue light has been scattered out. The result is a stunning sunset with orange and yellow hues.

Scattering nitrogen and oxygen causes orange and reddish sunsets. The blush blood-red sunset is caused by pollution. For a red sky, aerosols, solid or liquid particles that originate from both natural processes and human activity, need to be suspended in the air. Natural aerosols are created from forest fires, minerals from sandstorms, sea spray, volcanic eruptions, and more. However, the number of aerosols produced by human activity outweighs natural aerosols. Human-generated aerosols can enter the atmosphere. Aerosols are also produced when molecules in a gaseous state enter the atmosphere and react with other chemicals. The small aerosol particles suspended in the air scatter radiation, removing the violets and blue hues and enhancing the red and orange ones. At some point, the air pollution is so bad that the sky is saturated to the point that you can no longer see the sun. 

Although aerosols saturate the overall sunset experience, the real truth is that excess pollution will ruin the environment. Junior Sean Tinio believes that “these sunsets are dubbed aesthetic by thousands, if not millions of people out there, including himself.” He believes that many people love to exploit these sunsets for somewhat of an “aesthetic Instagram photo.” He thinks that “if everyone just took small steps, it could potentially reduce emissions released into the atmosphere over time.” In conclusion, Sean doesn’t think that he has seen a true sunset for a while, or if he has ever seen a true sunset. Sophomore Smriti Wadhwa believes that the truth is strange because most people “think that sunsets are the beauty of nature” but now, she feels “eager to never see a colorful sunset again if it means our Earth could be a cleaner place.”

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