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Oceanum Morocco ERA5 Wave Hindcast

February 2025

   
Model SWAN 41.31
Period Jun 1994 - Updating
Spatial resolution 0.05 degree
Temporal resolution 1 hourly
Region 19W - 6W, 22N - 38N
Forcings Reprocessed ERA5 winds, Glorys currents, and Oceanum spectra

Dataset description

The Morocco wave hindcast dataset provides a detailed account of ocean wave parameters across the Northwest African Atlantic coast, covering the waters from Western Sahara to the Strait of Gibraltar (Figure 1). The domain extends offshore to include the Canary and Madeira archipelagos, capturing their shadowing effects on wave propagation. Wave spectra are computed over a 30-year period between 1994 and present using the SWAN (Simulating WAves Nearshore) third-generation spectral wave model. The model is driven by inputs from the Oceanum Global Wave Model for spectral boundaries and reprocessed ERA5 winds from Copernicus Marine Service which incorporate scatterometer observations for improved accuracy, with ocean currents from the Glorys reanalysis. Bathymetry is derived from the GEBCO 2025 400 m grid.

The modelling setup employs the ST6 source term parameterisations. Spectra are discretised into 36 directional bins and 32 frequency bins, covering a frequency range from 0.037 to 0.7102 Hz with 10% logarithmic increments. The model features a regular grid with a 5 km (0.05 degree) resolution, spanning the entire Moroccan Atlantic coast and extending offshore to capture swell propagation from the North Atlantic.

The dataset provides hourly estimates for an extensive array of ocean wave parameters (Table 2) including spectral quantities integrated over the full spectrum and for spectral partitions (defined from an 8-second split and from the Watershed method). These data are stored over the entire grid at native resolution. Additionally, frequency-direction wave spectra are available at 738 sites, with resolution increasing from deep ocean areas towards the coast (see Figure 1).

Figure 1

Figure 1. Mean significant wave height from the Morocco hindcast domain. The locations of 2D spectra hourly output are shown by the black dots. Depth contours are shown at 50m, 200m, 1000m, and 3000m.


Validation

The wave hindcast can be validated against satellite altimeter observations using the Oceanum Hindcast Satellite Validation App. This interactive tool allows users to compare modelled significant wave height against satellite altimeter measurements at any location within the model domain, providing density scatter plots, quantile comparisons, and statistical metrics.


Data description

Table 1. Data description.

Field Value
Title Oceanum Morocco wave hindcast
Institution Oceanum
Access Oceanum Datamesh
Source SWAN 41.31A
Source terms ST6
Temporal coverage 1994-06-01 to present (updating)
Temporal resolution Hourly
Spatial coverage [19W, 22N, 6W, 38N] at 0.05 degree
Spectra output sites 738
Frequency discretisation 32 frequencies between 0.037 - 0.7102 Hz at 10% logarithmic increments
Direction resolution 10 deg
Bathymetry GEBCO 2025 Grid
Winds Reprocessed ERA5
Currents Glorys Reanalysis
Boundary Oceanum Global WW3 ERA5 hourly wave spectra

Linked Datamesh datasources


Integrated parameters gridded output

Integrated wave parameters are stored hourly over the domain at the native model resolution. Table 2 describes long names and units of all 38 gridded output parameters.

Table 2. Gridded output parameters.

Variable Long Name Units
depth depth below sea surface m
dpm mean direction at the spectral peak of wind and swell waves degree
dpmsea mean direction at the spectral peak of wind waves below 8 seconds period degree
dpmswe mean direction at the spectral peak of swell waves above 8 seconds period degree
dspr directional spreading of wind and swell waves degree
fspr normalised width of the frequency spectrum of wind and swell waves -
hs significant height of wind and swell waves m
hsea significant height of wind waves under 8 seconds period m
hswe significant height of swell waves above 8 seconds period m
pdir0 directional spreading of wind waves degree
pdir1 directional spreading of primary swell waves degree
pdir2 directional spreading of secondary swell waves degree
pdir3 directional spreading of tertiary swell waves degree
pdspr0 directional spreading of wind waves degree
pdspr1 directional spreading of primary swell waves degree
pdspr2 directional spreading of secondary swell waves degree
pdspr3 directional spreading of tertiary swell waves degree
phs0 sea surface wind wave significant height m
phs1 sea surface primary swell wave significant height m
phs2 sea surface secondary swell wave significant height m
phs3 sea surface tertiary swell wave significant height m
ptp0 sea surface wind wave period at variance spectral density maximum s
ptp1 sea surface primary swell wave period at variance spectral density maximum s
ptp2 sea surface secondary swell wave period at variance spectral density maximum s
ptp3 sea surface tertiary swell wave period at variance spectral density maximum s
pwlen0 mean wavelength of wind waves m
pwlen1 mean wavelength of primary swell waves m
pwlen2 mean wavelength of secondary swell waves m
pwlen3 mean wavelength of tertiary swell waves m
tm01 mean absolute wave period of wind and swell waves from the first frequency moment s
tm02 mean absolute wave period of wind and swell waves from the second frequency moment s
tps smooth relative peak wave period of wind and swell waves s
tpssea smooth relative peak wave period of wind waves below 8 seconds period s
tpsswe smooth relative peak wave period of swell waves above 8 seconds period s
xwnd eastward component of wind velocity m/s
ywnd northward component of wind velocity m/s

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