Polar cell

Definition

A polar cell is a type of atmospheric circulation that occurs in each hemisphere, characterized by rising air at the polar regions and sinking air at around 60 degrees latitude. This circulation is integral to understanding how temperature variations at the poles influence global weather patterns and climate conditions. Polar cells help drive the flow of polar easterlies and contribute to the overall structure of atmospheric circulation, impacting both local and global climates.

5 Must Know Facts For Your Next Test

1. Polar cells are driven primarily by the cooling of air at the poles, which causes it to become denser and sink.
2. The sinking air in the polar regions leads to high-pressure systems, while rising air at around 60 degrees latitude creates low-pressure systems.
3. These cells significantly influence weather patterns in the polar regions, including the formation of polar easterlies, which can impact storm paths.
4. Polar cells operate in conjunction with the Ferrel and Hadley cells, creating a complex web of atmospheric circulation that affects global climate.
5. The interaction between polar cells and warmer air masses can lead to significant weather events, such as cold fronts moving southward from polar regions.

Review Questions

• How do polar cells contribute to global atmospheric circulation?
  • Polar cells play a crucial role in global atmospheric circulation by creating high-pressure systems near the poles and low-pressure systems around 60 degrees latitude. This balance helps to establish wind patterns, such as the polar easterlies, which influence other circulation cells like the Ferrel and Hadley cells. Together, these interactions help distribute heat and moisture around the planet, significantly impacting weather and climate.
• Discuss the significance of rising and sinking air in polar cells and its effect on local weather conditions.
  • In polar cells, rising air at around 60 degrees latitude leads to low-pressure systems that often result in precipitation and stormy weather. Conversely, sinking air at the poles creates high-pressure zones with drier and more stable conditions. This dynamic is essential for understanding how temperature differences drive weather patterns, as the contrast between warm and cold air can lead to significant weather events, especially as these cells interact with mid-latitude systems.
• Evaluate the implications of changes in polar cell dynamics on global climate change.
  • Changes in polar cell dynamics due to global climate change can have widespread implications for Earth's climate system. As temperatures rise, alterations in the strength or position of polar cells can lead to shifts in wind patterns and precipitation distribution. This could exacerbate extreme weather events, impact ecosystems, and alter ocean currents, ultimately contributing to feedback loops that accelerate climate change effects. Understanding these connections is vital for predicting future climate scenarios.

Related terms

Ferrel Cell:

A mid-latitude atmospheric circulation cell located between the Hadley cell and the polar cell, characterized by prevailing westerlies.

Hadley Cell:

The tropical atmospheric circulation cell that extends from the equator to about 30 degrees latitude, where warm air rises and cools, resulting in precipitation.

Coriolis Effect: The apparent deflection of moving objects (like air) caused by the rotation of the Earth, influencing wind direction and patterns.