https://eo4society.esa.int/projects/waposal/
The WAPOSAL project has created an innovative application of Earth Observation data. WAPOSAL is creating a state-of-the-art database of wave renewable energy in European coastal zones and in marginal territories such as archipelagos, Africa, and the Mediterranean Sea, to support the EU Green Transition and achieve climate neutrality.
The new database is publicly available in the CEOS catalog at https://ceos.org/mim-database/ in the ESA Earth Code repository:
https://esa-earthcode.github.io/tutorials/waposal/
The WAPOSAL database contains coastal wave resource data at every 300 m for the regions of Figure 1: Along-track wave power density data, along-track wave power density trend data, wave period, coefficients of variability at specific coastal sites, dataset on the average distribution of the seasonal and wave power density and data on the distribution of the wave power density trend per coastal zone.
The global coverage of the altimetry constellation, the provision of significant wave height measurements, and the capability to estimate wave periods demonstrate that satellite altimeters are valuable systems for assessing the site-specific wave energy potential. WAPOSAL uses a novel methodology to compute wave power density based on a newly produced EO dataset that enables high-resolution multi-mission altimetry data in the coastal zone.
Objectives:
- Create a state-of-the-art dataset of average wave power density
- Obtain along-track wave period estimates in European coastal zones
- Obtain along-track wave power density estimates, their variability, and trends
Satellite altimetry missions have brought a new perspective and paved the way for renewable energy assessment from space. High-resolution SAR altimetry (Altimetry Virtual Lab-AVL) products from the ESA CryoSat-2, Sentinel-3, and Sentinel-6 Michael Freilich missions, and from the OCRE EO database, were processed with coastal zone algorithms such as SAMOSA+, offering a new opportunity to improve coastal wave energy assessments.
Significant wave height (Hs) and the backscatter coefficient (Sigma0) are directly derived from the OCRE-EO database distributed by the ESA AVL hosted on the EarthConsole® platform (https://earthconsole.eu/virtual-labs/).
Main achievements from WP1:
- The Gommenginger et al. (2003) method was successfully applied and improved to estimate the along-track wave periods required for wave power density.
- The method shows a good correlation for both the significant wave height (Hs) and the wave period (Tz) in all WAPOSAL regions (Figure 1).
- The statistical metrics of CryoSat-2 and Sentinel-3AB altimeters yield similar results.
- The uncertainty of the WAPOSAL database differs from one region to another. In the case of the Mediterranean Sea, it is 4.2 %.
Main achievements from WP2:
- The along-track wave power density by coastal zone, the wave power density variability in the selected coastal site, and the along-track wave power density and current comparison were assessed. The results show a strong correlation between ocean current magnitude and wave power density (see section Results).
- Main achievements from WP3:
- The wave power density and trend were assessed locally near the coast and along the tracks using 11 years of Sentinel-3A/B and CryoSat-2 data.
- The wave power density trend and variability estimated along coasts in selected locations indicate that, in general, some areas present a more favourable scenario (positive trends and low variability) for ensuring the future extraction of wave resources.
- WAPOSAL identified the best locations for installing WECs near the coast.
- An along-track database was created for the eleven regions of the study. It contains crucial information from observations that might help advance the green energy transition.
- The wave power density and trend were assessed near the coast and along the tracks.
- Seasonal and average wave power density maps were constructed in the coastal zone.
- Seasonal and average wave power density trend maps in the coastal zones