Photos of rare Nacreous clouds in the UK have been appearing in the news and on social media over the last couple of days and yesterday in the late afternoon we saw some from the garden.
The clouds are also known as Mother of Pearl clouds and form at temperatures of -78 degrees centigrade in the lower stratosphere (around 10 to 20 miles up whereas common clouds are around 5 - 6 miles above the surface of the Earth).
Beautiful they may be but they can be destructive - it is believed that they may speed up depletion of the ozone layers as the ice crystals in the cloud act as catalysts encouraging chemical reactions with the CFC gases released into the atmosphere which break down ozone.