section_path: Defining characteristics/Polar desert
section_name: Polar desert
paragraph_text: Polar desert
  
  Polar deserts are a type of cold desert. While they do not lack water, having a persistent cover of snow and ice, this is merely due to marginal evaporation rates and low precipitation.
  
  The McMurdo dry valleys of Antarctica, which lack water (whether rain, ice, or snow) much like a non-polar desert and even have such desert features as hypersaline lakes and intermittent streams that resemble (except for being frozen at their surfaces) hot or cold deserts for extreme aridity and lack of precipitation of any kind. Extreme winds and not seasonal heat desiccate these nearly-lifeless terrains.