A video has captured the rare "firefall" phenomenon at Yosemite National Park, where a waterfall appears to cascade molten lava.
The video, taken on February 22, shows Yosemite's Horsetail waterfall lit up as if alight with fire, from several angles.
This phenomenon is known as "Firefall." The illusion can only be seen from mid to late February every year in the California park. It occurs when the sun sets at a very specific angle, where the light hits the waterfall to create the effect that the water is on fire.
In the video, captured by Shreenivasan Manievannan, spectators can be seen waiting near a viewpoint, waiting to catch a glimpse of the rare phenomenon. As time moves on, the water suddenly becomes aglow as if set on fire. The glow of the waterfall also appears to deepen in color as the sun continues to set.
Every year Yosemite sees a spike in visitors as spectators gather at the California park in hopes of seeing the rare phenomenon.
However there are some strict criteria that must be met, in order for firefall to happen.
Firstly, it is very weather-dependent as the skies must be crystal clear for the sunlight to reach the water, tourist information site Yosemite.com says. During firefall season, there is a very small window of opportunity while the sun sets for the illusion to be created, so if clouds are cast over sun during this time, it does not happen.
It also depends on how much water is cascading down the cliff. The illusion only comes into full effect when there is enough water in Horsetail to reflect the light.
So there always has to be some snow on the ground, in order to feed water into the falls. But this also has to be paired with warm conditions so that this snow melts enough that it feeds into the waterfall.
It is still possible to see the glow of firefall if the conditions are cold, and there is only a little water flowing over the cliff, Yosemite reports. The light will still reflect on a small trickle of water. However, the illusion of flowing lava does not reach its full effect unless there is plenty of water falling over the cliff, as there is in this video.
Visitors can plan their visit to view firefall by looking up the water flow levels prior. The Yosemite Falls webcam presents a live feed of several areas of the national park, meaning potential spectators can look at Horsetail falls to gauge its water flow before arriving.
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Uncommon Knowledge
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Newsweek is committed to challenging conventional wisdom and finding connections in the search for common ground.
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Robyn White is a Newsweek Nature Reporter based in London, UK. Her focus is reporting on wildlife, science and the ... Read more
