As the song goes: Somewhere over the rainbow, bluebirds fly.
And misinformation does, too.
A viral TikTok, claiming to be voiced by actor Roseanne Barr, describes a conspiracy theory that rainbows, the kind that form in a sprinkler on a sunny day, result from toxins in the air and water supply.
“What the heck is in our water supply? What the heck is in our oxygen supply,” says the voice over a clip of a misting fountain with a rainbow. “What is oozing out of our ground that allows this type of effect to happen … This cannot be natural.” Text on the screen says “Roseanne Barr” and “conservative Republicans have officially lost their fking minds.”
But we followed this rainbow to its end and found that it’s not true. The audio is from an old video shared online in 2008 promoting a similar conspiracy theory — and there’s no evidence the voice is Barr’s.
Although she is known for her sensational comments, there is no record that Barr doubts the veracity or frequency of rainbows in her backyard. She shared a photo of a rainbow on her Instagram account to celebrate her November 2022 birthday.
Rainbows, besides being a fairytale staple, are a well-understood phenomenon caused by the refraction of light through water. When sunlight hits water droplets in the air, either after a rainstorm, on a foggy day or from a backyard mister, the different wavelengths of light are refracted and bent, causing them to show up as separate colors —– think Pink Floyd’s prismatic “Dark Side of the Moon” album cover.
The light then bounces off the water droplet and reflects the rainbow spectrum of light back where it originated. If the viewer is at the correct angle, the rainbow becomes visible.
It is this refraction and reflection that create the rainbows in the sky, not a chemical reaction, as the video claims.
Some scientists speculate that climate change may affect the frequency and coloration of rainbows because of changes in rainfall patterns as well as air pollution, which can affect how light scatters. But these theories are not related to a tainted water supply.
Despite the TikTok video’s colorful theory, there is no evidence that Barr made a video questioning the science of rainbows. We rate this claim False.