The Role of Stratosphere-Troposphere Planetary Wave Coupling in Driving Variability of the North Atlantic Circulation ...

• Main Author: Dunn-Sigouin, Etienne
• Format: Text
• Language: unknown
• Published: Columbia University 2018
• Subjects: Atmosphere; Physics; Stratospheric circulation; Atmospheric waves; Polar vortex; Heat flux; North Atlantic
• Online Access: https://dx.doi.org/10.7916/d84x5mcv; https://academiccommons.columbia.edu/doi/10.7916/D84X5MCV

The wintertime North-Atlantic exhibits enhanced circulation variability relative to other areas of the globe and is a key determinant of weather and climate in the highly populated regions of Europe and Eastern North America. Previous work has linked extreme stratospheric polar vortex and planetary wave heat flux events with variability of the North-Atlantic circulation. To elucidate the role of the stratosphere in driving variability of the North-Atlantic circulation, the goal of this thesis is to clarify the relationship between extreme planetary wave heat flux and vortex events and understand the dynamical mechanisms driving extreme stratospheric planetary wave heat flux events using an idealized model. The relationship between extreme stratospheric planetary wave heat flux and polar vortex events is clarified by comparing and contrasting their composite lifecycles using reanalysis data. Extreme negative heat flux events, defined as those less than the 5th percentile of the wintertime wave-1 distribution, ...