The International Polar Year (IPY) objectives are to seek major advances in knowledge and understanding and to obtain a snapshot of the current state of the Polar Regions. IPY focus on latitudes between 60 and 90° (both hemispheres) and any relevant region. The timeframe is set from 1st March 2007 to 1st March 2009. The project “Ozone layer and UV RAdiation in a changing CLimate Evaluated during IPY” (ORACLE-O3) is one of the coordinated international proposals selected for the IPY.

One part of this global project is called “Lagrangian Observations with Lidar Investigations and Trajectories in Antarctica and Arctic, of PSC (LOLITA-PSC)” and is devoted to Polar Stratospheric Clouds (PSC) studies. Understanding the formation and evolution of PSC particles is an important issue to quantify the impact of climate changes on their frequency of formation and, further, on chlorine activation and subsequent ozone depletion. For the first time, the “MATCH” method is applied to lidar observations of PSC. This lead to combine ground-based and space-borne lidar observations, with Lagrangian trajectory forecasts, in order to infer information on formation processes of each PSC type and assess our ability to predict PSCs for various environmental conditions. The campaigns take place in Antarctica during winters 2007 and 2008 and a pre-campaign was preformed in 2006 to test the methodology. At the final stage, microphysical model calculations will be performed for analysing the data and testing PSC formation scenarii along the trajectories. Correlations between evolutions of the air masses thermodynamical conditions and the type of PSC formed should arise.

Here we present the first results obtained for the 2006 pre-campaign. Lidar ground-based measurements are obtained for the three PSC lidar implemented in Antarctica, in the Dumont d'Urville (66.67°S, 140.01°E), Davis (68.00°S, 78.50°E) and McMurdo (77.86°S, 166.48°E). They are compared with CALIPSO space-borne lidar observations over Antarctica. All measurements are coupled using lagrangian trajectories calculations.