Study of the Artic Polar Vortex Erosion from Ozone Lidar Measurements Performed at OHP (44N,6E)

Abstract

Systematic stratospheric DIAL ozone measurements are performed at the Observatoire de Haute-Provence (OHP-44N,6E) with the use, since 1994, of the signals corresponding to the Nitrogen vibration raman scattering of the emitted laser radiations. In background aerosol conditions, the raman lidar signal can be used as a reference to optimize the rayleigh signals which allow to obtain accurate high resolution measurements in the low stratosphere. These measurements are used in the frame of the European METRO project which has for objective to study the mechanisms involved in the meridional transport of air from low and high latitudes to mid-latitudes region in the lower stratosphere, in order to understand the role of this transport in the ozone budget. More than 300 ozone profiles obtained in the winters 1996–1997, 1997–1998 and 1998–1999 were analysed in order to study the influence of filamentation processes (or laminae) due to the vortex erosion on the ozone amount at OHP. The detection of the filaments is made with a high resolution dynamical model developped at the Service d’ Aeronomie. The number of filaments overpasses observed at OHP are discussed in this paper as well as the temporal evolution of their magnitude during the winter, in relation with the polar processes in the Arctic vortex.