Stratospheric Aerosol and Gas Experiment II measurements of the quasi‐biennial oscillations in ozone and nitrogen dioxide

The first measurements ever to show a quasi‐biennial oscillation (QBO) in NO 2 have been made by the Stratospheric Aerosol and Gas Experiment II (SAGE II) and are presented in this work along with observations of the well‐known QBO in stratospheric ozone. The SAGE II instrument was launched aboard the Earth Radiation Budget satellite near the end of 1984. Measurements of ozone and nitrogen dioxide through early 1990 are analyzed for the presence of a quasi‐biennial oscillation. The measurements show the global extent of both the O 3 and NO 2 QBO in the 25‐ to 40‐km region of the stratosphere. The SAGE II QBO results for ozone compare favorably to theory and previous measurements. The QBO in NO 2 is found to be consistent with the vertical and horizontal transport of NO y . Both species exhibit a QBO at extratropical latitudes consistent with strong meridional transport into the winter hemisphere.