Final answer:
The Polar High creates polar desert/dry conditions at the poles due to very low precipitation rates, making these regions among the most extreme dry ecosystems on Earth.
Step-by-step explanation:
The Polar High creates polar desert/dry conditions at the poles. This is due to the cold temperatures that reduce the ability of air to hold moisture, leading to very low precipitation rates. Antarctic, for instance, is considered a desert because it averages fewer than 10 inches of precipitation per year. While coastal regions of Antarctica can receive up to four feet of snow annually, the interior near the South Pole might receive just a few inches. The cold and dry nature of polar regions contribute to them being one of the most extreme dry ecosystems on Earth, similar to hot deserts in terms of the paucity of precipitation.