Date of Award




Document Type

Master's Thesis

Degree Name

Master of Science (MS)


Department of Atmospheric and Environmental Sciences

Content Description

1 online resource (vii, 125 pages) : color illustrations, color maps.

Dissertation/Thesis Chair

Andrea L Lang

Committee Members

Brian H Tang


Predictability, Stratosphere, Stratospheric Polar Vortex, Synoptic, Wave Forcing, Polar vortex, Stratospheric circulation, Stratospheric winds, Rossby waves, Tropopause, Climatic changes

Subject Categories

Atmospheric Sciences


Major Sudden Stratospheric Warming (SSW) events are characterized by rapid warming of the polar regions at 10 hPa and are accompanied by a reversal of the 10-hPa zonal-mean zonal wind at 60˚N from westerly to easterly. Following an SSW event, stratospheric thermal and momentum anomalies can progress downward and linger near the tropopause for up to 60 days. These anomalies have major impacts on tropospheric sensible weather including increased likelihood of cold air outbreaks and heavy precipitation events. SSW events are largely forced by upward propagation of planetary-scale Rossby waves from the troposphere to the stratosphere. Synoptic-scale waves can contribute indirectly to the wave forcing but their role is not yet fully understood. A goal of this thesis is to understand the synoptic-scale contributions to sources of uncertainty the prediction of stratospheric polar vortex (SPV) variability, with a motivation to inform our interpretation of uncertainty in sub-seasonal wintertime forecasts of the troposphere.