Hurricane Ophelia has hit the UK and brought with it dust from the Sahara Desert and debris from forest fires in Spain and Portugal. The dust has caused shorter wavelength blue light to be scattered, leaving longer wavelength red light to shine through it. Ophelia originated in the Azores where it was classed as a hurricane. It has been tracked on its way northwards and has dragged in tropical air from the Sahara. The sky over my house in South Derbyshire this lunchtime turned dark and orange, almost apocalyptic and sent birds heading off to roost. By 3pm the sky was blue, bright sunshine and the cloud had disappeared.