01/07/2023
Unveiling Why Wildfire Smoke Turns Sunsets Deep Red
Image: Wildfire Sun, Easton, New York
Nature never ceases to amaze with its captivating displays of beauty, and one such phenomenon is the transformation of sunsets into a breathtaking deep red hue when wildfire smoke fills the sky. As the sun bids farewell for the day, it paints the horizon with vibrant colors. However, when wildfires rage, something magical occurs, engulfing the setting sun in an otherworldly crimson cloak. Let us explore the science behind this captivating phenomenon. It’s important to remember that these colorful sunsets are the byproduct of a horrible wildfire cycle that starts earlier, lasts longer and gets more destructive every year. As exogenous climate change further enhances the wildfire cycles in the coming decades, these deep red sunsets, sunrises, and milky skies will become prevalent.
Understanding Wildfire Smoke Composition:
To comprehend why wildfire smoke alters the colors of sunsets, we must first delve into its composition. Wildfire smoke consists of countless tiny particles, such as ash, soot, and other aerosols, which are released when vegetation and organic matter combust during wildfires. These particles are carried high into the atmosphere by the heat and convective currents generated by the fire.
Interaction of Light with Smoke Particles:
When sunlight interacts with the smoke particles suspended in the atmosphere, a fascinating interplay begins. The light we perceive as white actually comprises a spectrum of colors, each with a different wavelength. These colors include red, orange, yellow, green, blue, and violet. The shorter-wavelength colors, like blue and violet, scatter more easily in the atmosphere, while longer-wavelength colors, like red and orange, tend to pass through with less scattering.
Scattering and Absorption of Light:
As sunlight passes through the layers of smoke particles, the shorter-wavelength colors scatter more due to their interaction with the smaller-sized particles. This scattering effect causes the sky to appear hazy or even grayish. Simultaneously, the longer-wavelength colors, particularly red and orange, have a higher likelihood of being absorbed or refracted by the smoke particles rather than being scattered.
Reddish Light Dominance:
The absorption and refraction of shorter-wavelength colors leave the longer-wavelength colors to dominate the scene. Consequently, during sunset, when sunlight passes through a greater portion of the atmosphere, the remaining red and orange light undergoes less scattering and reaches our eyes relatively unhindered. This unique atmospheric condition, combined with the presence of wildfire smoke, intensifies the reddish hues during sunsets, creating a mesmerizing display of deep reds, oranges, and pinks.
The Role of Particle Size and Composition:
The size and composition of the smoke particles also play a crucial role in sunset colors. Larger particles tend to scatter light more effectively, resulting in a diffusion of colors. However, smaller particles—typical of wildfire smoke—preferentially scatter the shorter-wavelength colors, allowing the longer-wavelength reds and oranges to dominate. Additionally, the composition of the smoke particles can further influence the colors observed, as different materials may absorb or reflect specific wavelengths of light differently.
Artistic Marvel and Ecological Reminder:
While wildfire smoke altering sunset colors is a breathtaking sight to behold, it is important to remember the ecological impact behind these phenomena. Wildfires, although nature's regenerative process in some cases, can have devastating consequences, endangering lives, destroying habitats, and emitting harmful pollutants. The red sunsets serve as a poignant reminder of the urgent need to address climate change, mitigate wildfires, and protect our natural ecosystems.
The transformation of sunsets into deep red masterpieces, under the influence of wildfire smoke, is a captivating reminder of the intricate dance between light and nature's elements. As sunlight traverses the smoke-laden atmosphere, the scattering and absorption processes selectively enhance the longer-wavelength red and orange light, painting the sky with an ethereal crimson glow. Let us appreciate the sheer beauty of this phenomenon while remaining mindful of the underlying environmental challenges we face in combating wildfires and safeguarding our planet.