3.4 A Case Study of 4D-VAR Data Assimilation in Southern Europe

摘要

This paper describes a case study on variational data assimilation of in-situ measurements at 260 stations in Central and Southern Europe, using the SILAM chemistry-transport model. The aim of the experiment was to investigate the emission distribution, and both initial concentration and emission correction factor were included in estimated parameters. The main improvement in forecasts due to assimilation was seen at sites with the worst model-measurement agreement. Throughout the assimilation period, the estimated emission rates for Mt. Etna and the surrounding volcanic areas were substantially smaller than those derived from the emission inventory. Subtler emission corrections were obtained for industrialised areas in Central Europe.