Читать книгу Polar Exploration. A practical handbook for North and South Pole expeditions онлайн

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Most people think of snow simply as frozen water, but it's far more complicated than that. Snow is actually a form of precipitation as ice crystals, hexagonal prisms that form when water freezes up. Prisms are formed because of the molecular structure of water. As these ice crystals are formed, they develop into one of the following:

DON'T EAT SNOW!

If you're wondering how to survive in the cold without any means of thawing ice or snow – it's important to know that it takes more energy to eat snow than it is worth. You use more energy eating it than you gain through hydrating your body with it.

 snow crystals Individual, single ice crystals, often with six-fold symmetrical shapes. These grow directly from condensing water vapour in the air, usually around a nucleus of dust or some other foreign material. Typical sizes range from microscopic to at most a few millimetres in diameter.Measuring snow thickness on the Arctic Ocean

 snowflakes Collections of snow crystals, loosely bound together into a puffball. These can grow to large sizes (up to about 10cm across) when the snow is especially wet and sticky. A snowflake consists of up to a hundred snow crystals clumped together.Ice crystals in the polar regions deserve a closer look