Polar cell

Definition

A polar cell is a component of the Earth's atmospheric circulation that operates in the polar regions, characterized by descending cold air and the formation of high-pressure systems. This cell plays a crucial role in the overall dynamics of the atmosphere, interacting with other cells and influencing weather patterns in both polar and mid-latitude areas.

5 Must Know Facts For Your Next Test

1. The polar cell exists at both hemispheres and extends from about 60° latitude to the poles, with cold air sinking at the poles creating high-pressure areas.
2. Air descends in the polar regions leads to dry conditions, contributing to the formation of polar deserts, such as Antarctica.
3. The polar cell significantly affects global climate patterns, interacting with warmer air masses from lower latitudes, which can lead to storm formation in the mid-latitudes.
4. In summer, the polar cells weaken as temperatures rise, leading to more pronounced mixing of air masses and potential for unusual weather events in adjacent regions.
5. The boundaries of the polar cells are dynamic and can shift due to changes in temperature or atmospheric pressure, affecting weather patterns over large areas.

Review Questions

• How does the polar cell interact with other atmospheric circulation cells, such as the Ferrel and Hadley cells?
  • The polar cell interacts with both the Ferrel and Hadley cells through complex air movement and pressure systems. Cold air descending in the polar regions meets warmer air from lower latitudes, leading to convergence zones where significant weather events can occur. This interaction results in varying climate conditions at mid-latitudes, including storm tracks that are influenced by these opposing air masses.
• Evaluate the impact of the polar cell on weather patterns experienced in mid-latitude regions.
  • The polar cell greatly influences mid-latitude weather by creating contrasting temperature gradients between cold polar air and warmer subtropical air. This interaction often leads to cyclonic storms and frontal systems that are typical of mid-latitude climates. The dynamics between these cells contribute to variability in weather patterns, resulting in phenomena such as winter storms and seasonal shifts.
• Synthesize how changes in the strength or position of the polar cell may affect global climate trends.
  • Changes in the strength or position of the polar cell can have profound effects on global climate trends by altering jet stream patterns and shifting storm tracks. A stronger polar cell might lead to more persistent cold conditions in polar regions while influencing atmospheric pressure systems across continents. Conversely, a weakening polar cell could allow for warmer air to infiltrate higher latitudes, potentially contributing to rapid climate changes such as melting ice caps and altered precipitation patterns globally.

Related terms

Hadley Cell:

A large-scale atmospheric circulation pattern found in tropical regions, where warm air rises at the equator and cools as it moves poleward, creating low-pressure zones at the equator and high-pressure zones around 30° latitude.

Ferrel Cell:

The Ferrel cell is an atmospheric circulation cell located between the Hadley and polar cells, characterized by rising air in the mid-latitudes and sinking air at higher latitudes, contributing to prevailing westerly winds.

Jet Stream: A fast-flowing ribbon of air high in the atmosphere that influences weather patterns and is closely associated with the boundaries between different atmospheric cells, including the polar cell.