Description of the data

This dataset captures the variability of stratospheric polar vortex in the Southern Hemisphere (SH). It is derived using the zonal mean zonal winds at 55-65°S, 10 hPa and averaged over the spring months, i.e. September to November, when the polar vortex variability is largest. The dataset is based on the reanalysis data set ERA5 and for the period 1959-2021. The stratosphere is known to provide some measurable long-range predictability to the eddy-driven jet via the vertical coupling between the stratosphere and the troposphere.