A non-linear expression of the North Atlantic Oscillation in the North Pacific

The North Atlantic Oscillation (NAO) has been identified as an important mode of variability in the climate system. Our knowledge of its impacts is based largely on linear analysis techniques. As a result, non-linearities associated with it are largely unknown. In this study, we use recently proposed non-linear compositing and one-sided regression techniques as well as a new rectified regression technique to show that the non-linear expression of the NAO is fundamentally different from its linear expression. In particular, we show that its non-linear expression is amplitude but not sign dependent and has a center of action in the North Pacific sector that is associated with the East Asia jet stream (EAJS) and the Aleutian Low.