Wildfires are raging across the United States and devastating the environment and communities. They have also turned the skies orange-red that conjure up images of the apocalypse. Comparisons have also been made to Mars, the movie “Blade Runner 2049” and the shows “Stranger Things” and “Avatar: The Last Airbender.”
Parts of Washington, Oregon, California, Idaho, Nevada, Arizona, and Utah are under the significant and elevated risk of fire weather, according to the National Weather Service, and people going outside are also urged to check their local AQI (air quality index) to conclude if the air is safe.
According to NASA, the color-changing skies are a consequence of smoke particles, which block certain wavelength colors from the sun:
The smoke particles from the fires allow sunlight’s longer wavelength colors like red and orange to get through while blocking the shorter wavelengths of yellow, blue and green. Those longer wavelengths give the sky a red or orange tinted appearance. Similarly, during sunrise and sunset times when the sun is near the horizon, sunlight has to travel through more of Earth’s atmosphere to get to you. The additional atmosphere filters out the shorter wavelengths and allows the longer wavelengths to get through, providing reds and oranges during those times. [source]
Opened the door this morning in SF. Sky in California is really this orange pic.twitter.com/erJB2ENTPY
— Carla (@DoctorWC) September 9, 2020
San Francisco right now: a sickly orange glow pic.twitter.com/iZQ99oUGqG
— Peter Aldhous (@paldhous) September 9, 2020