A link between tropical intraseasonal variability and Arctic stratospheric ozone

Abstract

Previous studies using satellite measurements showed evidence that subtropical upper troposphere/lower stratosphere ozone (O 3) can be modulated by tropical intraseasonal variability, the most dominant form of which is the Madden Julian Oscillation (MJO) with a period of 30-60 days. Here we further study the MJO modulation in the upper troposphere/lower stratosphere O 3 over the northern extratropics and the Arctic. Significant MJO-related O 3 signals (13-20 Dobson units) are found over the northern extratropics (north of 30°N). The O 3 anomalies change their magnitude and patterns depending on the phase of the MJO. Over the Arctic, the MJO-related O 3 anomalies are dominated by a wave number 2 structure and are anticorrelated with the geopotential height (GPH) anomalies at 250 hPa. The latter is similar to the findings in the previous studies over subtropics and indicates that the Arctic upper troposphere/lower stratosphere O 3 anomalies are associated with dynamical motions near the tropopause. The teleconnection from the tropics to the Arctic is likely through propagation of planetary waves generated by the equatorial heating that affects the tropopause height and O 3 at high latitudes. Key Points Intraseasonal signals of Arctic O3 (~10 DU) correlated with tropical influencesTeleconnection through barotropic propagation of planetary wavesTeleconnection in tracers to better predict air qualities at higher latitudes ©2013. American Geophysical Union. All Rights Reserved.