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Why do polar regions have low temperatures and relatively low precipitation?

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World map with continents shaded in colors representing climate zones, from warm reds and yellows near the equator to cool blues and whites at the poles. — Climate Even in our warming world, there will be some chilly evenings.

Polar regions experience low temperatures and limited precipitation due to several key meteorological factors:

Low Temperatures

The primary driver of cold temperatures is the low solar elevation angle at high latitudes, which causes solar energy to be spread over a larger surface area, resulting in less intense heating. Additionally, the cooling of surface air layers leads to the formation of polar anticyclones, which are high-pressure systems characterized by clear, cold weather. During winter, the polar vortex—a large area of persistent low pressure—further traps and maintains masses of extremely cold air over these regions.123

Low Precipitation

Precipitation is limited primarily by the relationship between temperature and atmospheric moisture capacity. Because the air in polar regions is extremely cold, its capacity to hold water vapour is significantly reduced; at temperatures below −40 °C, water vapour can account for less than one-fifth of 1 percent of the air's volume. While these regions are often compared to deserts due to low annual precipitation, they differ because the persistent cold limits evaporation, allowing the limited moisture to be retained in the environment.45