DR KEITH WHEELER / SCIENCE PHOTO LIBRARY DR KEITH WHEELER / SCIENCE PHOTO LIBRARY
Trees covered in hoar frost. Hoar frost forms from air that is supersaturated with water vapour. This can occur when moist air cools rapidly. For hoar frost to form, the temperature of the surface on which the deposition occurs has to be below the freezing point of water. This results in the formation of many needle-like ice crystals. Hoar frost forms in still, clear and cold weather. Photographed in Exmoor, Devon, England.
Model release not available. Property release not required.