Dynamic Scaling of Bred Vectors in Chaotic Extended Systems

We argue that the spatiotemporal dynamics of bred vectors in chaotic extended systems are related to a kinetic roughening process in the Kardar-Parisi-Zhang universality class. This implies that there exists a characteristic length scale corresponding to the typical extend over which the finite-size perturbation is actually correlated in space. This can be used as a quantitative parameter to characterize the degree of projection of the bred vectors into the dynamical attractor.