Logo del Dipartimento

Logo UniGe

DICCA MeteOcean Re-Analysis 1979-2016

The MeteOcean group at DICCA has performed a re-analysis of atmospheric and wave conditions, producing an hindcast database spanning from January 1979 till the end of December 2016 over the domain employed for the atmospherical and wave condition simulations.
The hindcast dataset for wave characteristics can be employed for Coastal and Ocean Engineering studies and researches. DICCA MeteOcean group is willing to collaborate and share its knowledge for research and consulting projects.
Meteorological re-analyses have been developed employing NCEP Climate Forecast System Reanalysis, CFSR for the period from January 1979 to December 2010 and CFSv2 for the period January 2011 to December 2016.

For some available application and service see the section below. For any enquires please write to giovanni.besio(at)unige.it

If you are interested in hindcast data please refer to the following map in order to identify grid points of interest

Parameters provided by the hindcast

Hindcast grid points are provided in multicolumn ASCII format. Every column corresponds to a different physical parameter and every line is referred to consecutive time steps (1 hour steps from 01/01/1979 till 31/12/2016). Parameters are stored as:

YYYY mm dd HH:MM:SS Hs Tm Tp Dirm Dirp Spread Lm Lp uw vw Hsws Tmws Dirws s1Hs s1Tm s1Dir s2Hs s2Tm s2Dir

YYYY - Year
mm - month
dd - day
HH - hour
MM - minutes
SS - seconds
Hs - Significant Wave Height [m]
Tm - Mean Period [s]
Tp - Peak Period [s]
Dirm - Mean Direction [°N]
Dirp - Peak Direction [°N]
Spread - Directional Spreading [°]
Lm - Mean Wavelength [m]
Lp - Peak Wavelength [m]
uw - West-East Wind Velocity [m/s]
vw - South-North Wind Velocity [m/s]
Hsws - Wind Waves Significant Height [m]
Tmws - Wind Waves Mean Period [s]
Dirws - Wind Waves Mean Direction [°N]
s1Hs - First Swell Wave Height [m]
s1Tm - First Swell Mean Period [s]
s1Dir - First Swell Mean Direction [°N]
s2Hs - Second Swell Wave Height [m]
s2Tm - Second Swell Mean Period [s]
s2Dir - Second Swell Mean Direction [°N]

WRF domain
WRF simulation domain

The numerical models

The numerical model chain employed in this study consists in a meteorological model for the reanalysis and simulation of winds and atmospheric fields and a third generation model for the description of generation and propagation of wind and swell waves in the Mediterranean basin.

The wind model

The wind forcing employed in the simulations has been provided by the 10-m wind fields obtained using the non-hydrostatic mesoscale model WRF-ARW version 3.3.1 (Skamarock et al., 2008).
A single computational domain has been implemented for the WRF model, covering the whole Mediterranean with a ~10 km resolution Lambert conformal grid.
Initial and boundary conditions for the atmospheric simulations with the WRF model were provided from the CFSR (Climate Forecast System Reanalysis) database (Saha et al., 2010). Use of CFSR wind field reanalysis for wave modeling proved to compare well with measurements even though sometimes it is possible to miss the highest wave events (e.g. Chawla et al., 2013; Cox et al., 2011; Splinder et al., 2011).
Simulations has been performed by means of 24-hr-long WRF simulations, with outputs saved every hour, updating the analysis every 24 hours, whereas the boundary conditions were imposed every three hours. This kind of approach leads to unavoidable discontinuities in the wind fields every 24 hours. However, we believe that this is a minor drawback since the influence of such discontinuity on the wave field is reasonably small due to the delayed response of wave growth and development to the wind forcing.
On the other way, making a continuous WRF simulation would certainly trigger signicant errors in the wind output, since longer term forecasts progressively drift away from reality, compensating the advantage of eliminating discontinuities.
WavewatchIII domain
WavewatchIII simulation domain

The wave model

The re-analysis of wave conditions relies on the third generation wave model WavewatchIII, version 3.14 (Komen et al., 1994; Tolman, 2009), for the description of wave generation and evolution processes of the wave field.
Following the set-up employed for wind simulations, WWIII has been implemented in the Mediterranean basin on a regular grid (hereinafter referred to as R10) with a resolution of 0.1273×0.09 degrees, corresponding almost to 10 km at the latitude of 45°N, and ETOPO1 data has been used for the interpolation on the computational grid of the bathymetry.
The model has been forced with the wind fields obtained from the atmospheric model with an hourly time step.
Validation of the hindcast has been developed through the comparison between the numerical results and wave buoy observations, employing integrated parameters such as the significant wave height Hs, the mean wave period Tm and the mean propagation direction θm (see Mentaschi et al., 2013; Mentaschi et al., 2015).

Re-analysis simulations output are recorded hourly in all points of the computation grid for both meterological and wave quantities.

Coastal and Ocean Engineering Applications

Hindcast dataset can be used in order to perform researches and studies in the field of Coastal and Ocean Engineering. The availability of an extended time serie with a good spatial resolution allows in fact to have a detailed and reliable knowledge of wave climate in any point of the numerical domain (i.e. inside the Mediterranean Sea). It is then possible to perfom all kind of analysis on the wave data for Metocean Engineering purposes, ranging from offshore structure design to coastal morphodynamics studies.

Available Products

Time series and all derivative products can be delivered in ASCII format and final reports can be provided. For any enquire please contact giovanni.besio (at) unige.it

Below we show some possible application developed by DICCA MeteOcean group.

Wave climate characterization

Extreme wave height values analysis

Alghero Extreme Levels
Extreme wave height analysis
for Alghero hindcast point
Alghero Extreme Levels
Extreme wave height analysis for
Mazara del Vallo hindcast point
The wave hindcast serie has been employed in order to perform an evaluation of extreme values for significant wave height along the Italian coast. A direct comparison has been performed between data obtained by the re-analysis numerical simulation done by DICCA MeteOcean group and the data provided by the network of buoys for wave measurement along the italian coast (Rete Ondametrica Nazionale RON).
Once the comparison and validation has been performed on the RON historical data, and the hindcast dataset has confirmed its reliability, an extensive analysis for significant wave height and return periods has been developed. This kind of analysis can be performed in any chosen location inside the Mediterranean Sea giving an useful and reliable analysis tool for Maritime and Coastal Engineers.
Wave climate assessment and characterization can be performed on the same dataset, giving useful information for wave regimes characterization for coastal processes and sediment transport analysis.

Wave energy assessment for renewable energy projects

Annual Mean Wave Energy Flux
Annual Mean Wave Energy Flux 1979-2014
Autumn Mean Wave Energy Flux Winter Mean Wave Energy Flux
Spring Mean Wave Energy Flux Summer Mean Wave Energy Flux
Seasonal Mean Wave Energy Flux 1979-2014
A detailed and reliable knowledge of wave energy resource in the offshore region is of great importance to characterize and define areas where it would be convenient and suitable the development of wave energy harvesting, making profitable and suitable local site project planning and design. The development of a wave hindcast simulation for extended period (1979-2015) allows to give a detailed insight about the wave energy resource available in the Mediterranean basin, identifiying and characterizing the most interesting area for energy exploitation. The evaluation is carried out on the basis of a wave hindcast simulation covering the period 1979-2015 with ouput recorded on a hourly basis. With high resolution in space (almost 10 km) and time (1h) it is possible to perform detailed analysis of wave potential characteristics in the whole Mediterranean basin, providing information on seasonal and longer term variability necessary for reliable and optimal design of wave energy extraction equipment.

DICCA - Dipartimento di Ingegneria Civile, Chimica e Ambientale
Via Montallegro, 1 - 16145 Genova
tel. +39 010 353.24.91 fax +39 010 353.25.46
Partita IVA 00754150100