Cerca nel sito per parola chiave

pubblicazioni - Presentazione

Investigating the influence of model coupling by comparing CAMx and WRF-CHEM over Italy

pubblicazioni - Presentazione

Investigating the influence of model coupling by comparing CAMx and WRF-CHEM over Italy

In questo lavoro sono presentati i primi risultati del modello accoppiato di meteorologia e qualità dell’aria WRF/Chem e il confronto con il modello di chimica e trasporto CAMx sul territorio italiano per il mesi di gennaio e giungo 2005

The impact of climate change on air quality may affect future air quality policy planning, especially in urban areas, through modifications of gas-phase chemistry, transport, removal processes and natural emissions (Giorgi and Meleux, 2007). Modern air quality models, such as CAMx (ENVIRON, 2008), do not allow the estimation of the coupled interactions between climate change and air quality and, hence, their effects on policies. Otherwise, in the fully coupled Weather Research and Forecasting/Chemistry model (WRF-Chem, Grell et al., 2005) the chemistry transformations are embedded into WRF (Skamarock et al., 2008), so that such interactions can be investigated with a full modular approach. In this contribution we present the simulation results over Italy of two different modelling systems, WRF/CAMx and WRF-Chem, whose performances have been evaluated both in terms of meteorology and chemistry. Italy often suffers high ozone and PM concentrations, due to the interaction of both anthropogenic and biogenic emissions, enhanced by rather complex circulation conditions, making it a very interesting case study. CAMx is a well-known state of art chemistry transport model extensively applied over the Italian domain, thus representing an interesting benchmark for a WRF-Chem application. Models have been applied over the Italian Peninsula with a grid step of 15 km, for both January and June 2005. ECMWF fields have been used to initialize WRF and WRF-Chem. Anthropogenic emissions have been derived from both Italian and EMEP emission inventories. The MEGAN (Guenther et al., 2006) model has been used to estimate biogenic emissions. As a first step, computed meteorological fields have been compared to ground level observations as well as vertical profiles. Then, CAMx and WRF-Chem results have been compared to an extensive dataset of 397 air quality stations, providing observations of O3, PM10 and PM2.5 and their main precursors to assess possible differences in both transport and chemistry. Finally, some analyses of PM chemical composition have been carried out too. For each evaluation step, the influence of the different model formulation is presented and discussed.

Progetti

Commenti