A surreal and rare spectacle unfolded across parts of Britain on Wednesday morning as a soft pink fog descended, transforming the dawn landscape into a scene of ethereal beauty. The unusual phenomenon was captured in locations like Dunsden in Oxfordshire, where country lanes disappeared into a rosy haze at daybreak.
The Science Behind the Rosy Glow
This captivating display is a striking example of atmospheric physics in action. According to meteorologists, the effect occurs when sunlight passes through layers of fog during sunrise or sunset. Fog, essentially a cloud at ground level, is composed of countless tiny water droplets suspended in the air.
These droplets scatter the shorter wavelengths of sunlight – the blues and greens – more effectively than the longer red wavelengths. When the sun is low on the horizon, its light travels through a greater thickness of the atmosphere, enhancing this filtering process. The result is that the remaining red light dominates, bathing the fog in a distinctive pink or rosy hue.
"'Pink fog' is a phenomenon that occurs when sunlight passes through layers of fog during sunrise or sunset," a Met Office spokesperson explained. "It's important to note that pink fog is purely an optical effect. It does not indicate any unusual weather hazard beyond normal fog risks, such as reduced visibility."
Perfect Conditions for a Rare Sight
The event on Wednesday was prompted by a specific set of weather conditions. Overnight temperature drops led to the formation of widespread fog across a large swathe of central and northern England. The Met Office issued a yellow weather warning, which remained in effect until 10am, cautioning that the fog would be slow to clear and could lead to difficult travel conditions.
Patches of particularly dense fog formed across the East Midlands and Cambridgeshire, significantly reducing visibility. However, in areas where the fog's thickness was just right, the magical pink effect took hold.
Dr Claire Ryder, an associate professor at the University of Reading, emphasised the rarity of the sight. "This effect is caused by a reddish sunrise being 'filtered' by the fog," she said. "It's quite interesting and rare: you need the fog to occur at the exact sunrise or sunset time, and also for the fog to consist of a perfect thickness... Too thick a fog would block out all the light, and too thin a fog wouldn't mute the sunrise colours very much."
A Brief History of Pink Fog in the UK
While Wednesday's display was remarkable, it was not entirely unprecedented. A similar event was recorded in 2019 when early morning fog across parts of south-west England also took on a pinkish tint. These occurrences serve as a vivid reminder of the intricate and often beautiful interactions between light, water, and our atmosphere.
For residents and early-morning travellers in Oxfordshire and beyond, the surreal sight provided a momentary distraction from the travel disruptions, offering a unique and memorable start to the day. The phenomenon underscores how ordinary weather events can, under the perfect alignment of conditions, create extraordinary visual wonders.
