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Alpine glow

A beautiful illumination effect seen in mountainous regions around sunset, beginning when the sun is around 2º above the horizon. At its most spectacular, snow-covered mountains in the east assume vivid tones of yellow, pink and purple.
 

Air

The mixture of gasses that make up the Earth’s atmosphere. Excluding water vapour and dust, the main components of air are nitrogen, oxygen, argon, carbon dioxide, neon, helium, krypton, hydrogen, xenon and ozone.

Advection fog

A type of fog formed when warm, moist, stable air moves over a far cooler surface. It is most commonly found over cool sea areas in spring and summer, but does occasionally form over land in the winter, especially when the ground is frozen or covered by snow.