GREENVILLE, N.C. (WNCT) — During the summer months, it is not uncommon for smoke from wildfires and Saharan dust to travel through different portions of the United States. With smoke and dust particles present at the surface, beautiful sunsets can occur with the right weather conditions present.
Smoke and dust are both different forms of particulate matter smaller than 2.5 micrometers and cannot be seen with the human eye. Scientists call this PM 2.5, which is a form of pollution. With more dust and smoke particles flying around in the sky, more sunlight is being scattered in all directions.
The colors we see throughout our atmosphere are directly dependent on traveling sunlight. Although sunlight appears clear, it is made up of all colors with different wavelengths. Blue has the shortest wavelength and red has the longest.
The wavelength of a color can be compared to the distance a color can travel. For example, during the day the sun is directly above earth at a 90 degree angle. Sunlight has to travel a shorter distance to make it to earth with blue being the first color scattered out. During sunset hours, light has to travel a farther distance because it is not directly above earth’s surface.
Because this light has to travel farther during sunset, more and more particles get in the way, scattering out more color. Now, when smoke and dust come into play, there are even more particles scattering out even more color.
That’s why the deepest and most vibrant hues of reds, pinks, and oranges are seen making a spectacular sunset with smoke and dust in the atmosphere.