Abstract: The observed characteristics of the 4-day eastward-moving wave 1 in the Southern Hemisphere polar winter stratosphere are surveyed using ten years of National Meteorological Center (NMC) geopotential height data. The 4-day ...

Abstract: AbstractLong-term changes in upper-tropospheric jet latitude, altitude, and strength are assessed for 1980?2014 using five modern reanalyses: MERRA, MERRA-2, ERA-Interim, JRA-55, and NCEP CFSR. Changes are computed from ...

Abstract: The stability of a basic state composed of a westward-moving wave and a zonal mean jet is examined in a linearized barotropic nondivergent model on a sphere. The sensitivity of the stability to the strength and structure ...

Abstract: AbstractLong-term changes in upper-tropospheric jet latitude, altitude, and strength are assessed for 1980?2014 using five modern reanalyses: MERRA, MERRA-2, ERA-Interim, JRA-55, and NCEP CFSR. Changes are computed from ...

Abstract: The stability of basic states consisting of a jet similar to the stratospheric polar night jet and a traveling wave with a single zonal wavenumber is examined in a linearized nondivergent barotropic model on a sphere. Basic ...

Abstract: The stability of realistic jets is examined in a linearized barotropic model on a sphere. Approximately non-dispersive modes associated with a region of negative basic state absolute vorticity gradient on the poleward side ...

Abstract: novel diagnostic tool is presented, based on polar-cap temperature anomalies, for visualizing daily variability of the Arctic stratospheric polar vortex over multiple decades. This visualization illustrates the ubiquity ...

Abstract: version of the Canadian Middle Atmosphere Model (CMAM) that is nudged toward reanalysis data up to 1 hPa is used to examine the impacts of parameterized orographic and nonorographic gravity wave drag (OGWD and NGWD) on the ...