Influence of lower stratospheric ozone variation on tropospheric temperature and mean meridional circulation in the Northern Hemisphere summer

Through statistical analyses of observational data, the study examined the influence of the lower stratospheric ozone variation on the troposphere in the Northern Hemisphere mid-latitude summer. It was found that an increase in the lower stratospheric ozone strengthens static stability at the tropopause. Thus, the vertical wave propagation is trapped there more efficiently. The zonal flow deceleration due to the wave forcing induces anomalous residual mean circulation. This causes anomalous cooling in the troposphere through anomalous upward motion to the south of 60 degrees N and less latent heating to the north. As a result, the tropospheric temperature decreases vis-a-vis the increase in stratospheric ozone. A sensitivity experiment was carried out using an AGCM to examine the tropospheric responses to the increase in stratospheric ozone. The result shows responses similar to the observations. The consistence between the observation and AGCM suggests a climate change in the troposphere induced by stratospheric ozone variation. Citation: Nakamura, T., H. Akiyoshi, and Y. Yamashita (2009), Influence of lower stratospheric ozone variation on tropospheric temperature and mean meridional circulation in the Northern Hemisphere summer, Geophys. Res. Lett., 36, L14701, doi:10.1029/2009GL038563.