FTP, name these temperate patterns of atmospheric circulation surrounding the Polar cells.
The high latitude ends of these phenomena are commonly disrupted by Omega Blocks and Rossby Waves at lower levels, contributing to their weakness.  Most efficient in the spring and autumn, the descent and divergence of winds at their low-latitude ends provides the poleward component of the mid-latitude westerlies, and at their tropopausal level they are responsible for the motion of cooled air towards the equator.  FTP, name these temperate patterns of atmospheric circulation surrounding the Polar cells.
The high latitude ends of these phenomena are commonly disrupted by Omega Blocks and Rossby Waves at lower levels, contributing to their weakness.  
Ferrell cells