Annual and interannual variability of tropical-extratropical interaction: an empirical study.

Abstract

It has been hypothesized that regions of upper tropospheric equatorial westerlies act as efficient ducts or corridors for transient and stationary extratropical modes deep into the tropics and even to the other hemisphere. Furthermore, it has been argued that the degree of efficiency depended upon the strength of the local equatorial westerlies, thus inducing a probable distinct seasonal and interannual variability in interactions between the hemispheres and between the extratropics and low latitudes. These hypotheses are tested in the present study using an 11 yr National Meteorological Center (NMC) climate data set.-from Authors