Summary
As part of the global project ORACLE-O3 selected for the IPY, LOLITA-PSC (“Lagrangian Observations with Lidar Investigations and Trajectories in Antarctica and Arctic, of PSC”) is devoted to Polar Stratospheric Clouds (PSCs) studies. Indeed, understanding the formation and evolution of PSCs 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. In this framework, three lidar stations performed PSC observations in Antarctica during the 2006, 2007, and 2008 winters: Davis (68.58°S, 77.97°E), McMurdo (77.86°S, 166.48°E) and Dumont D’Urville (66.67°S, 140.01°E). The dataset also includes the space-borne lidar data from the CALIOP/CALIPSO instrument. Lagrangian trajectory calculations are used to identify PSCs air masses sounded by several ground-based lidar stations with the MATCH methodology, originally applied to investigate ozone depletion from balloon-borne soundings. Different trajectory models, grids and initializations have been used to test the robustness of an identified MATCH. The evolution of the optical properties of the PSCs and thus the type of PSCs formed could thus be linked to the thermodynamical evolution of the air mass along the trajectories. Microphysical modelling based on the DMI (Danish Meteorological Institute) box model complements the Lagrangian approach with PSC characterization (PSC particle type and geometrical properties) for various environmental conditions. We also use a high resolution transport model coupled to a microphysical model containing a fully explicit size-resolving microphysical scheme to test the influence of different trajectories on the results of the model and produce global PSC fields. The ability to calculate the optical properties from the particle size distribution allows for quantitative comparisons between the lidar measurements and the microphysical modelling. This combined approach can help in investigating the dynamical evolution and the formation of the particles within the air mass.