Eddy-Induced Instability for Low-Frequency Variability

Abstract:

Synoptic eddy–mean flow interaction has been recognized as one of the key sources for extratropical low-frequency variability of the atmospheric circulation. The underlying dynamics of this interaction can be examined from the perspective of a synoptic eddy-induced dynamic instability. In this talk, we first briefly review the concept of “noise” induced instability and “eddy-induced dynamic instability”. We also show numerical simulations of this instability and discuss the role of this instability in generating leading modes of extratropical low-frequency variability.