Naslov
Does increasing the resolution of Mesoscale Numerical Weather Prediction models enhance reproduction of wind regimes in the complex terrain?

Autori
Hrastinski, Mario ; Horvath, Kristian ; Odak Plenković, Iris ; Ivatek-Šahdan, Stjepan ; Bajić, Alica

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Skup
5th International Conference on Meteorology and Climatology of the Mediterranean

Mjesto i datum
Istanbul, Turska, 02.03.2015. - 04.03.2015

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
complex terrain; local winds; ALADIN model; statistical verification; spectral verification

Sažetak
In the complex terrain of Eastern Adriatic where wind climate is governed by regional/local winds, it is beneficial to utilize a chain of numerical models to refine the associated wind predictions. The principal questions we address are i) whether an increase of model resolution improves the accuracy and ii) could simplified and computationally cheaper Mesoscale Numerical Weather Prediction (MNWP) models be used in the model chain for assessment and forecasting of wind properties? To answer the above questions, wind forecasts from Aire Limitée Adaptation dynamique Développement InterNational (ALADIN) MNWP model with 8 km horizontal grid spacing were used in period 2010-2012. Those forecasts were further refined to 2 km grid spacing using: i) full physics based model, and ii) so-called dynamical adaptation method (DADA) over subdomain that covers broader area around Croatia. Statistical and spectral verification were performed for three different forecasting setups using measured wind speeds from several meteorological stations that represent different climate regions of Croatia. Based on variety of statistical scores and spectral measures inferred in frequency domain, it is suggested that the results generally improved with increasing the model resolution. The largest portion of errors can be attributed to phase errors, while the most significant increase of accuracy was found for diurnal periods of motions. Furthermore, a correlation between phase error and spectral measures of model performance at different temporal scales was found. Simplified DADA forecasts have proven to be valuable in forecasting wind propertirs on majority of stations, except for those near the very coast and steep terrain where full-physics based model was more successful in representing regional/local wind systems. Finally, kinetic energy, vorticity and divergence spectra were analyzed to provide a scale-dependent measure of model performance as well as to study the gross effects of horizontal diffusion on the effective model resolution.

Izvorni jezik
Engleski

Znanstvena područja
Geologija

Napomena
IPA projekt WILL4WIND, IPA2007/HR/16IPO/001-040507

POVEZANOST RADA