Climatological study of the total ozone field around the subtropical jet stream

Abstract

AbstractA study of the average distribution of total ozone was accomplished for the period from October 1982 to September 1983 in the area 20–50°N, 90–160°E, i.e. the entrance region of the East Asian subtropical jet stream. Total ozone data were obtained from the Total Ozone Mapping Spectrometer on the Nimbus‐7 satellite.Normally, the subtropical jet stream (STJ) marks a steep gradient in total ozone. From the monthly mean study of total ozone and wind fields at the 200 hPa surface, it was found that in winter the total ozone contours are almost parallel to the wind directions; the horizontal gradient in total ozone increases as the wind speed strengthens. In winter and spring, a sharp gradient in total ozone is found on the cyclonic side of the STJ because of the strong Hadley circulation. As the Hadley cell ceases in summer, the jet weakens and horizontal gradients in total ozone become much smaller, disappearing almost entirely by early autumn.