MOdello COAMPS...

[Fabry74]

...che è?...un nuovo modello?...non ne sapevo dell'esistenza!Meteociel - Modèle Numérique américain COAMPS

[Marc0]

sarà già un mesetto almeno che su meteociel c' è questo modello

lo seguo appunto da un pò ma non mi pare molto performante

[bufera87]

hai qualche dato a tal proposito?sarebbe da vedere le caratteristiche del modello...

[bufera87]

pare invece sia peformante con accoppiamento oceano-atmosfera...

On the Improvement of COAMPS Weather Forecasts Using an Advanced Radiative Transfer Model

Navy's Coupled Ocean-Atmosphere Mesoscale Prediction System (COAMPS)1 to calculate solar and thermal infrared fluxes in 6 shortwave and 12 longwave bands. The model performance is evaluated at high resolution for clear-sky and overcast conditions against the observations from the Southern Great Plains of the Atmospheric Radiation Measurement Program. In both cases, use of the Fu-Liou model provides significant improvement over the operational implementation of the standard Harshvard-han radiation parameterization in both shortwave and longwave fluxes. A sensitivity study of radiative flux on clouds reveals that the choices of cloud effective radius schemes for ice and liquid water are critical to the flux calculation due to the effects on cloud optical properties. The sensitivity study guides the selection of optimal cloud optical properties for use in the Fu-Liou parameterization as implemented in COAMPS. The new model is then used to produce 3-day forecasts over the continental United States for a winter and a summer month. The verifications of parallel runs using the standard and new parameterizations show that Fu-Liou dramatically reduces the model's systematic warm bias in the upper troposphere in both winter and summer. The resultant cooling modifies the atmospheric stability and moisture transport, resulting in a significant reduction in the upper-tropospheric wet bias. Overall ice and liquid water paths are also reduced. At the surface, Fu-Liou reduces the negative temperature and sea level pressure biases by providing more accurate radiative heating rates to the land surface model. The error reductions increase with forecast length as the impact of improved radiative fluxes accumulates over time. A combination of the two- and four-stream options results in major computational efficiency gains with minimal loss in accuracy.


e poi

Model of atmosphere COAMPS - LOSSEB

Model of atmosphere COAMPS Weather forecast model: weather forecast part of The Coupled Ocean/Atmosphere Mesoscale Prediction System – COAMPS (Naval Research Laboratory, Monterey, California)


COAMPS is initialized by the data of Navy Operational Global Atmospheric Prediction System (NOGAPS).
The atmosphere part of COAMPS is used for modelling the area of Central Europe with the entire Baltic Sea in the Interdisciplinary Centre for Mathematical and Computational Modelling (ICM), University of Warsaw.
The model is realized in 30 vertical layers, with computation, among others, of the all parameters needed for further driving the hydrodynamic and wave models, among others:
albedo fraction,

• turbulent kinetic energy,
• cloud base height,
• cloud ceiling height,
• total cloud coverage,
• dewpoint depression,
• latent, sensible and total heat flux,
• geopotential height,
• relative humidity,
• total precipitation,
• pressure,
• long wave, net, solar, total radiation,
• vapor pressure,
• air temperature,
• visibility,
• wind components (incl. vertical velocity),
• wind stress components.

• We initialize our version on initial and boundary conditions from ICM
• We run the model on the set of nested grids, as shown in the map

inoltre ho notato che i campi sono ben delineati, e non tutti dritti il chè significa che la griglia è piuttosto piccola...

[Marc0]

io da quando le seguo non l'ho mai visto azzeccare anche a sole 48 ore, ma ok, mi fiderò dei dati.

[bufera87]

è possibile che sia in fase di "tuning" con le varie parametrizzazioni da sistemare bene... ma dici che ha sbarellato a 48 ore?quando?e cosa intendi dire? che i campi previsti non sono poi stati verificati nella realtà?