Contributions of downstream baroclinic development to strong Southern Hemisphere cut?off lows

Cut-Off Lows (COLs) in the Southern Hemisphere and mechanisms involved their development are investigated detail using eddy kinetic energy (EKE) budget applied to data from ERA-Interim reanalysis. This approach considers most important processes that typical for evolution of midlatitude disturbances such as baroclinic (BRC) barotropic (BRT) conversions, ageostrophic flux convergence (AFC), known downstream development. Composites volume-integrated EKE its components evaluated based on 200 intense SH COLs (>98th percentile) observed a 36-year period. Results show AFC together with BRC conversion contributors growth COLs, characterizing The plays an role genesis intensification phases while is system maintenance. dissipation occurs due dispersive fluxes (ageostrophic divergence) other not directly computed equation, friction latent heat release which problematic reanalysis datasets. BRT contributes negatively COL by transferring zonal flow energy, though this enough dampen intensification. Regional differences were found energetics, indicating originating upstream continents clearly dominated fluxes, systems over Australian region mostly driven processes.