Latest news with #HermannvonHelmholtz
BBC News
26-03-2025
- Climate
- BBC News
Rare wave clouds captured in North Yorkshire sky
A rare cloud formation resembling waves in the sky has been seen across North billowy phenomenon was captured on camera in Cawthorn on Tuesday night by a BBC weather as Kelvin-Helmholtz clouds, they form when a faster stream of air moves above rising air to the Met Office website, Kelvin-Helmholtz clouds are "an extremely rare phenomenon". They are named after two physicists - Hermann von Helmholtz and William Thomson, who was also known as Lord Kelvin - studied the physics behind cloud Met Office said: "Kelvin Helmholtz clouds, or fluctus clouds, are quite rare."These clouds are more likely to be seen on windy days when there is a difference in density of the air."They also indicate instability in the atmosphere, which can help identify areas of turbulence for aircraft."They added: "This phenomenon, whilst rare, has also been spotted in cloud patterns on Jupiter, within Saturn's bands and on the sun's corona." Listen to highlights from North Yorkshire on BBC Sounds, catch up with the latest episode of Look North.
Yahoo
25-02-2025
- Climate
- Yahoo
Waves in the sky: Kelvin-Helmholtz clouds spotted in Canada
A woman in Calgary, Alberta, Canada, saw a strange, wavy cloud in the sky on Feb. 22, 2025, and took to X, formerly known as Twitter, to crowdsource an answer. "Does anyone know what is happening here? I saw this cloud formation this afternoon in Calgary looking to the west. It's a first for me." Anne Wilkie posted on X. What she saw was a Kelvin-Helmholtz wave cloud, named after Hermann von Helmholtz, who discovered the atmospheric instability that leads to this phenomenon. These waves in the sky are formed similarly to ocean waves, where high winds blow over the water, sculpting the flat water into wave formations. In the atmosphere, which acts similar to a fluid, this happens between two layers of different air densities. Kelvin-Helmholtz instability has also been spotted on the sun and Saturn. While these wave clouds typically form in clear conditions, as Wilkie saw in Calgary, they can also form ahead of thunderstorm shelf clouds of severe thunderstorms in rare instances, as shown in the photo below. Kelvin-Helmholtz wave clouds, ahead of a thunderstorm shelf cloud in Roanoke, Illinois, in June of 2006. (AccuWeather/marygarrels) The AccuWeather photo blog also featured Kelvin-Helmholtz wave clouds seen over the Big Horn Mountains near Sheridan, Wyoming, on Dec. 6, 2022. Kelvin-Helmholtz wave clouds at Big Horn Mountains near Sheridan, Wyoming, Dec. 6, 2022. (Rachel Gordon)
