LAGRANGIAN FORECASTING DURING ASHOE MAESA - ANALYSIS OF PREDICTIVE SKILL FOR ANALYZED AND REVERSE-DOMAIN-FILLED POTENTIAL VORTICITY/

A statistical analysis is conducted to determine to what extent analyz ed and 5-day reverse-domain-filled (RDF) potential vorticity (PV) obta ined from meteorological analyses can predict ATLAS nitrous oxide (N2O ) tracer structure encountered along the ER-2 flight track during the Airborne Southern Hemisphere Ozone Experiment/Measurements for Assessi ng the Effects of Stratospheric Aircraft (ASHOE/MAESA) campaign. The r esults indicate that RDF PV shows no statistically significant improve ment in forecast skill over analyzed PV in predicting tracer structure along the ER-2 flight track. In fact, RDF generally shows a degradati on in predictive skill. RDF does show some success in refining large-s cale gradients and small-scale structures, present in the analyzed PV fields. In at least one case, RDF PV captured a filament encountered b y the ER-2, but in general, such structure is marked by low confidence in the RDF PV analyses.