Professor Gloria Manney, Northwest Research Associates and New Mexico Tech
Andrea Simpson (andrea.simpson@physics.ox.ac.uk)
Abstract
While impacts of broad measures of sratospheric polar vortex strength on climate and extreme weather events have been widely studied, less attention has been given to the impacts of stratospheric polar vortex variations on upper troposphere / lower stratosphere (UTLS) circulation and composition and how the UTLS contributes to that stratospheric influence on the surface. This talk uses diagnostics of stratospheric polar vortex geometry / strength combined with regionally and seasonally varying characterisation of tropopauses and UTLS jets to show links between stratospheric polar vortex variability and regional variations in UTLS jet and tropopause characteristics. Results will show UTLS jet and tropopause characteristics for strong and weak stratospheric vortex states (defined using vortex-focused metrics that are less dependent on geometry and position than commonly used diagnostics), as well as regional variations in correlations between polar vortex and jet diagnostics. Preliminary work will be shown assessing impacts of these vortex, jet, and tropopause relationships on regional UTLS ozone and water vapour variations diagnosed from composition reanalyses and satellite datasets.