Early risers across central and northern England were treated to a surreal spectacle on Wednesday morning as a soft pink fog descended upon the countryside, casting an ethereal glow at daybreak.
The Science Behind the Rosy Glow
This unusual atmospheric display, captured in locations like Dunsden in Oxfordshire, is a striking but purely optical phenomenon. According to meteorologists at the Met Office, 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 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 more of the Earth's atmosphere, enhancing this scattering effect. The result is that the remaining red light dominates, bathing the fog in a distinctive pink or rosy hue.
Perfect Conditions for a Rare Sight
Dr Claire Ryder, an associate professor at the University of Reading, emphasised the rarity of the event. She explained that multiple conditions must align perfectly for the pink colour to manifest clearly.
"This effect is caused by a reddish sunrise being 'filtered' by the fog," Dr Ryder said. "The sunrise produces the red light, by removing the bluer colours, and then the small fog droplets scatter the light more, dimming the effect, giving it a muted pink glow."
She noted that the fog must occur at the exact time of sunrise or sunset and consist of a precise thickness, droplet concentration, and droplet size. Too thick a fog would block all light, while too thin a fog would not sufficiently mute the sunrise colours.
Travel Disruption Amid the Beauty
Despite its captivating appearance, the Met Office was quick to clarify that the pink fog posed no unusual hazard beyond the standard risks associated with dense fog, primarily severely reduced visibility. The agency had issued a yellow weather warning for a large swathe of central and northern England, which remained in effect until 10am.
The warning highlighted that the fog would be slow to clear and advised caution for travellers. Patches of particularly dense fog formed across the East Midlands and Cambridgeshire, where difficult driving conditions were reported.
This is not the first time the UK has witnessed this phenomenon; a similar event was recorded in 2019 when early morning fog turned the sky pink over parts of south-west England. However, each occurrence remains a fleeting and memorable moment where the simple physics of light transforms the familiar British landscape into a scene of otherworldly beauty.
