Assessment of trends in an intergrated climate metric-Analysis of 200 mbar zonal wind for the period 1958-2021

Abstract: Using the ERA5 and JRA-55 reanalysis datasets on latitude bands of nearly equal area, we analyze the trend of 200 mbar zonal wind anomalies for the period 1958-2021 as well as annual-mean latitude of the polar jet stream. We find basically no change of 200 mbar zonal wind in either the JRA-55 or ERA5 dataset. In addition, the polar jet core moves poleward in the Northern Hemisphere, but the movement is not statistically significant, while no poleward shift at all has occurred in the Southern Hemisphere.