This project aims to quantify the underlying dynamics and the predictability of the life cycle of blocked regimes. Enhanced predictability may be expected in particular for regimes of planetary scale. However, the correct representation of regime life cycles is a major challenge in current NWP models. In particular, the onset of blocking is harder to predict than its decay.
Both nonlinear Rossby wave dynamics and cloud diabatic processes have been demonstrated to play major roles during the life cycle, but our understanding of the interactions between both and the associated sensitivities in the overall evolution are still insufficient.
The PV anomaly and the PV error associated with this blocked regime are investigated based on a quantitative PV framework (Teubler and Riemer 2016, Baumgart et al. 2018). This framework is able to capture wave dynamics, as quasi-barotropic RWP propagation, baroclinic interaction and diabatic processes (indirect via divergent outflow).
- Baumgart, M.A., M. Riemer, F. Teubler, V. Wirth, and S.T.K.Lang, 2018: Potential-vorticity dynamics of forecast errors: A quantitative case study, Mon. Wea. Rev.,146.5, 1405?1425
- Teubler, F., and M. Riemer, 2016: Dynamics of Rossby wave packets in a quantitative potential vorticity–potential temperature framework. J. Atmos. Sci., 73, 1063–1081