Spatial growth of perturbations in turbulent baroclinic flows

Stability theories have traditionally been applied to mid-latitude atmospheric shear flows to understand the growth of forecast errors. Relatively less attention has been devoted to the spreading rate of localized disturbances in complex time dependent flows. This problem is explored here through numerical experiments using a spectral QG model for a turbulent jet flow and the spread and propagation rates of these disturbances in relation to a tracer are compared. The spreading rates of localized disturbances are sensitive to the structure of the initial disturbance and its location with respect to synoptic features. These results will be compared with those for straight flows in an attempt to assess the effect of the transience and non-linearity.