Sujet Les perles de Youtube

mais ça ne me paraît pas totalement délirant comme comportement. Qui respecte le code de la route à 100% ?

On ne parle pas du tout des angles morts avant. Lesquels sont devenus de plus en plus importants au fur et à mesure que les pare-brises s'inclinaient pour l'aérodynamique (et le look) et que la taille des montants augmentait. Au point d'être devenus largement assez gros pour cacher un 2 roues, voire une voiture à l'approche d'un rond point.

Crown flash is a rarely observed weather phenomenon involving "The brightening of a thunderhead crown followed by the appearance of aurora-like streamers emanating into the clear atmosphere".[1] The current hypothesis for why the phenomenon occurs is that sunlight is reflecting off or refracting through tiny ice crystals above the crown of a cumulonimbus cloud. These ice crystals are aligned by the strong electro-magnetic effects around the cloud,[2] so the effect may appear as a tall streamer, pillar of light, or resemble a massive flash of a searchlight / flashlight beam through the clouds. When the electro-magnetic field is disturbed by electrical charging or discharges (typically, lightning flashes) within the cloud, the ice crystals are re-orientated causing the light pattern to shift, at times very rapidly and appearing to 'dance' in a strikingly mechanical fashion.[3] The effect may also sometimes be known as a "leaping sundog". As with sundogs, the observer would have to be in a specific position to see the effect, which is not a self-generated light such as seen in a lightning strike or aurora, but rather a changing reflection/refraction of the sunlight.

The first scientific description of a crown flash appears to be in the journal Monthly Weather Review in 1885[4], according to the Guinness Book of Records[5]. Also mentioned in Nature in 1971[6] and in a letter to Nature slightly earlier in the same year,[7] this phenomenon is regarded as rare and not well documented. Starting in 2009 several YouTube videos have since emerged that appear to document this phenomenon.[8]