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The purpose of the COSMO Newsletter is: 1.) to review the present state of the model system and its operational application and to give information on recent changes; 2.) to present the principal events concerning COSMO during the last year and to summarize recent research and development work as well as results from the model verification and diagnostic evaluation; 3.) to provide the meteorological community and especially all external users of the model system with information on COSMO's activities and with new information on the model system and its current forecast quality.

COSMO Newsletter No. 19

The Technical Reports are intended mainly for internal use within the COSMO group (COSMO = Consortium for Small Scale Modeling), but also to inform other groups on model changes and research activities. The purpose of the Technical Reports is 1. to document scientific research activities, 2. to document technical changes to the model system, 3. to give an overview on new components of the model system.

Una parte significativa della costa emiliano-romagnola è soggetta all’erosione. Il fenomeno ha iniziato a interessare il litorale a partire dai primi decenni del ‘900, ma ha raggiunto la maggior intensità nella seconda metà del secolo. Per tenere sotto controllo le spiagge minacciate dai fenomeni erosivi, la Regione Emilia-Romagna ha istituito agli inizi degli anni ’80 le reti di monitoraggio dell’intero litorale regionale, gestite da Arpae, che controllano: l’evoluzione della linea di riva e la variazione della morfologia di spiaggia e fondale (rete topo-batimetrica), le variazioni tessiturali dei sedimenti di spiaggia (rete sedimentologica) e, infine, l’abbassamento del suolo (rete della subsidenza). Il volume presenta i risultati dell’ultima campagna di rilievo topo-batimetrico e sedimentologico della costa regionale eseguita dall’Unità Mare e Costa di Arpae nel 2012. Esso rappresenta il quinto studio dell’evoluzione costiera regionale e dei processi che su di essa insistono condotto per conto della Regione Emilia-Romagna. L’elaborazione dei dati di monitoraggio e l’utilizzo di alcuni indicatori dello stato della costa, messi a punto da Arpae e applicati sui 117 km di costa con arenile, ha permesso di identificare 84 km di litorale in buone condizioni, mentre i rimanenti 33 km presentano varie condizioni di criticità. L’estensione dei tratti critici sarebbe stata ben più rilevante (77 km) senza gli interventi messi in atto dalla Regione e dagli Enti Locali, e in particolare l’apporto, tra il 2006 e il 2012, di circa 2,8 milioni di mc di sabbia per ripristinare le spiagge. L’analisi dei dati di monitoraggio conferma l’efficacia del ripascimento nel contrasto all’erosione e nel mantenimento delle spiagge, ma evidenzia anche che i fenomeni erosivi si sono intensificati nel tempo, rendendo quindi necessario aumentare gli sforzi per limitarne l’entità.

Given the new parametrization adopted at ECMWF (European Center for Medium Weather Forecasts - Shinfield Park Reading U.K.) with a closure based on a quasi-equilibrium assumption for convective motions, a strategy can be adopted to compare high resolution non-hydrostatic models either with explicit convection or different convective parametrization. In fact the ECMWF forecasts with the NEW convective parametrization are distributing the moist energy to the convective activity with different mechanisms arising from the sensitivity of the moist energy to surface and boundary layer processes that act to differentiate their adjustment time scale. The effect of using different initial surface condition to start and to trigger convection, can be compared in real cases where surface and boundary layer conditions seem to be the main trigger of convective events. One outcome of this is how the equilibrium and non-equilibrium condition could be imposed in numerical weather prediction models (NWP) that have different parametrization and if this can help to forecasts better deep convective events.

A hierarchy of medium (2 km) and high (0.5 km) resolution operational models cast in the Adriatic sea (NE Mediterranean Sea), relying on an updated core w.r.t. previously existing one, characterized by having a wide variety of applications ranging from civil protection to scientific ones, is presented and described. The computing core of the system sits at Hydro-Meteo-Clima Service (SIMC, Bologna), and the scientific supervision is provided by DISVA Polytechnic University of Marche and CNR-ISMAR Venice. The core of the operational system is based on the Regional Ocean Modeling System, version 3.4. The hydrodynamic variables (e.g. sea surface elevation, currents, temperature, salinity, storm surge height) , and wave parameters are predicted every day for the next 72 hours. The surface forcing for the hydrodynamic (AdriaROMS 4.0) and wave (SWAN) operational models is derived from the predicted results of the operational meteorological model COSMO-I7 (7 km resolution) which forecasts atmospheric fields over the whole Italian seas. Hydrodynamic results are verified against oceanographic and wave buoys, tide gauges, bottom mounted acoustic current meter profilers, available in the coastal waters of the Adriatic Sea and oceanographic surveys. More specifically, CNR-ISMAR in the northern Adriatic Sea manages a meteo-oceanographic buoy network and the fixed ocean observatory tower "Acqua Alta", SIMC manages a wave buoy. Aiming to obtain forecast improvements in coastal areas of northern Adriatic Sea, a newly implemented, more resolved (0.5 km) ROMS version two-way coupled with SWAN is nested in the operational AdriaROMS 4.0 covering the Adriatic Sea at 2 km horizontal resolution. Outputs of operational models drive dedicated submodels for oil-spill transport and dispersion, coastal morphodymanic, sediment transport, saline wedge, water quality.

The Technical Reports are intended mainly for internal use within the COSMO group (COSMO = Consortium for Small Scale Modeling), but also to inform other groups on model changes and research activities. The purpose of the Technical Reports is 1. to document scientific research activities, 2. to document technical changes to the model system, 3. to give an overview on new components of the model system.

The Technical Reports are intended mainly for internal use within the COSMO group (COSMO = Consortium for Small Scale Modeling), but also to inform other groups on model changes and research activities. The purpose of the Technical Reports is 1. to document scientific research activities, 2. to document technical changes to the model system, 3. to give an overview on new components of the model system.