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Atmos. Chem. Phys. Discuss., 6, 11299-11316, 2006
www.atmos-chem-phys-discuss.net/6/11299/2006/ doi:10.5194/acpd-6-11299-2006 © Author(s) 2006. This work is licensed under a Creative Commons License. |
Interannual variability and long term changes in planetary wave activity in the middle atmosphere observed by lidar
Service d’Aéronomie/IPSL, CNRS, UVSQ, UPMC, France
Abstract. The upwelling planetary wave activity (PW) from the troposphere controls the intensity of the equator to pole transport of stratospheric ozone by the Brewer-Dobson circulation and thereby modulates the total ozone content at mid- and high-latitudes. Rayleigh lidar temperature data obtained from 1981 to 2001 at mid-latitude were used to study the interannual variability of PW activity in winter (October to April). The spectrum of stratospheric temperature fluctuations exhibits 2 peaks corresponding to 2 dominant modes of free travelling Rossby waves known as 16 day- and 12 day-waves. The 12 day-wave activity is shown to be anticorrelated with the equatorial QBO wind at 40 hPa. During the period 1981–2000 the global PW activity shows a negative trend for months October to January and a positive trend in March and April.
Citation: Hauchecorne, A., Keckhut, P., and Chanin, M. L.: Interannual variability and long term changes in planetary wave activity in the middle atmosphere observed by lidar, Atmos. Chem. Phys. Discuss., 6, 11299-11316, doi:10.5194/acpd-6-11299-2006, 2006.