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Figure 7. Time series of offshore significant wave height (a), peak period (b) and mean wave direction (c) obtained from CMEMS (https: / /marine.copernicus.eu/, accessed on 28 June 2021), and 15-day moving average (red). Time-series of the relative 1.05 m (MSL) shoreline proxy advance seawards (warm colors) or retreat landwards (cold colors) (d) along the coastal stretch from Vagueira (0 m) to Barra (9500 m). The relative advance or retreat is in comparison with the shoreline proxy position surveyed on 3 December 2020 (reference situation before storm Dora). Horizontal black lines refer to groynes and to breakwater. Beach accretion after storm Dora is displayed in Figure 7d. In this Figure, each shore line proxy relative position is compared with the shoreline proxy position on 3 December (before storm Dora). Two major patterns emerged in Figure 7. First, the shoreline proxy 1.05 m (MSL) rapid y moved landwards at the downdri 2021 onward. Second, the shoreline proxy continued backed up by dunes (those located southwards of G5). At those locations, there are no clear patterns of to al recovery because the circles are s ft side of G2 and of G3 from January to moved landwards on beaches till associated with negative values The shoreline proxy close to Vagueira beach started to display some values close to 0 m on March 2021. This indicates that the 1.05 m (MSL) con relative position a natural behaviour. our has recovered its 3 December that location, which can be in part ascribed to the Vagueira beach

Figure 7 Time series of offshore significant wave height (a), peak period (b) and mean wave direction (c) obtained from CMEMS (https: / /marine.copernicus.eu/, accessed on 28 June 2021), and 15-day moving average (red). Time-series of the relative 1.05 m (MSL) shoreline proxy advance seawards (warm colors) or retreat landwards (cold colors) (d) along the coastal stretch from Vagueira (0 m) to Barra (9500 m). The relative advance or retreat is in comparison with the shoreline proxy position surveyed on 3 December 2020 (reference situation before storm Dora). Horizontal black lines refer to groynes and to breakwater. Beach accretion after storm Dora is displayed in Figure 7d. In this Figure, each shore line proxy relative position is compared with the shoreline proxy position on 3 December (before storm Dora). Two major patterns emerged in Figure 7. First, the shoreline proxy 1.05 m (MSL) rapid y moved landwards at the downdri 2021 onward. Second, the shoreline proxy continued backed up by dunes (those located southwards of G5). At those locations, there are no clear patterns of to al recovery because the circles are s ft side of G2 and of G3 from January to moved landwards on beaches till associated with negative values The shoreline proxy close to Vagueira beach started to display some values close to 0 m on March 2021. This indicates that the 1.05 m (MSL) con relative position a natural behaviour. our has recovered its 3 December that location, which can be in part ascribed to the Vagueira beach

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Table 1. General characteristics of shoreface nourishments in previous works. In 1992, a shoreface nourishment of about 1.0 x 10° m3 was built at Newport Beach, California, US [19]. The shoreface nouris nmen was placed in water depths between —4 to —9 m (MSL). Offshore wave conditions along the California coastline are characterized by an averaged offshore significant wave heigh summer and in winter, respectively. Large swel common at this site with an averaged pea Ayo can reach or exceed 5 m offshore but sheltering effect close to Newport Beach towards the southeast direction [19] and itise [20]. he tid K Wav (Ho) that ranges from 1.75 m to 3.5 min waves generated in the Pacific Ocean are e period (T,) of 12.3 s [20]. During storms, ffectively reduced due to Channel Islands The wave-induced sediment transport is al range is about 2 m during spring tides. Overall, this nourishment moved onshore likely due to wave action. While the outer limit of the shoreface nourishment moved offshore (i.e., beach width increase) abou about 180 m onshore, the MSL contour moved 30 m in 2.5 yr (Figure 2 in [19]). Moreover, the
Table 1. General characteristics of shoreface nourishments in previous works. In 1992, a shoreface nourishment of about 1.0 x 10° m3 was built at Newport Beach, California, US [19]. The shoreface nouris nmen was placed in water depths between —4 to —9 m (MSL). Offshore wave conditions along the California coastline are characterized by an averaged offshore significant wave heigh summer and in winter, respectively. Large swel common at this site with an averaged pea Ayo can reach or exceed 5 m offshore but sheltering effect close to Newport Beach towards the southeast direction [19] and itise [20]. he tid K Wav (Ho) that ranges from 1.75 m to 3.5 min waves generated in the Pacific Ocean are e period (T,) of 12.3 s [20]. During storms, ffectively reduced due to Channel Islands The wave-induced sediment transport is al range is about 2 m during spring tides. Overall, this nourishment moved onshore likely due to wave action. While the outer limit of the shoreface nourishment moved offshore (i.e., beach width increase) abou about 180 m onshore, the MSL contour moved 30 m in 2.5 yr (Figure 2 in [19]). Moreover, the
Table 2. Shoreface nourishment onshore displacement (Son), MSL contour offshore displacement (Soff), and respective migration rates.
Table 2. Shoreface nourishment onshore displacement (Son), MSL contour offshore displacement (Soff), and respective migration rates.
Figure 1. Study area. Coastal defense works include two breakwaters at the Aveiro entrance channel, five groynes at the northern part of the study area and another at Vagueira beach and two revetments one close to G4 and the other at Vagueira beach. The area associated with the shoreface nourishment intervention was between G3 and G5. Beach profiles and topographic beach profiles were obtained within the COSMO programme. Coordinates are referred to the ETRS89 system. Figure 1. Study area. Coastal defense works include two breakwaters at the Aveiro entrance channel,
Figure 1. Study area. Coastal defense works include two breakwaters at the Aveiro entrance channel, five groynes at the northern part of the study area and another at Vagueira beach and two revetments one close to G4 and the other at Vagueira beach. The area associated with the shoreface nourishment intervention was between G3 and G5. Beach profiles and topographic beach profiles were obtained within the COSMO programme. Coordinates are referred to the ETRS89 system. Figure 1. Study area. Coastal defense works include two breakwaters at the Aveiro entrance channel,
Figure 2. Beach profiles at Vagueira (panel (a)) and at Costa Nova (panel (b)) beaches (yellow lines in Figure 1) between 2018 and 2020. Zoom-in of the submerged beach profiles (panels (c,d)). Standard deviation of beach profile elevations for each cross-shore position (panels (e,f)).
Figure 2. Beach profiles at Vagueira (panel (a)) and at Costa Nova (panel (b)) beaches (yellow lines in Figure 1) between 2018 and 2020. Zoom-in of the submerged beach profiles (panels (c,d)). Standard deviation of beach profile elevations for each cross-shore position (panels (e,f)).
Figure 3. Topographic beach profiles at Barra, Costa Nova, Vagueira 1 and Vagueira 2 beaches (red lines in Figure 1, from North to South) (top panels). Correlation coefficient between beach volume (per unit width) and the displacement of elevation contours (middle panels). Scatter diagrams between beach volume and the displacement of the 1.05 m (MSL) contour (bottom panels).
Figure 3. Topographic beach profiles at Barra, Costa Nova, Vagueira 1 and Vagueira 2 beaches (red lines in Figure 1, from North to South) (top panels). Correlation coefficient between beach volume (per unit width) and the displacement of elevation contours (middle panels). Scatter diagrams between beach volume and the displacement of the 1.05 m (MSL) contour (bottom panels).
Figure 4. Time evolution of the bathymetric contour associated with —10 m (MSL) (panel (a)) and with —8 m (MSL) (panel (b)). Coastal defense works over the study area (black) and the area associated with the shoreface nourishment intervention was between G3 and G5 (dashed white). Coordinates are referred to the ETRS89 system.
Figure 4. Time evolution of the bathymetric contour associated with —10 m (MSL) (panel (a)) and with —8 m (MSL) (panel (b)). Coastal defense works over the study area (black) and the area associated with the shoreface nourishment intervention was between G3 and G5 (dashed white). Coordinates are referred to the ETRS89 system.
Figure 5. Time series of offshore significant wave height (a), peak period (b) and mean wave direction (c) obtained from CMEMS (https: / /marine.copernicus.eu/, accessed on 28 June 2021), and 15-day moving average (red). Time-series of the relative 1.05 m (MSL) shoreline proxy advance seawards (warm colors) or retreat landwards (cold colors) (d) along the coastal stretch from Vagueira (0 m) to Barra (9500 m). The relative advance or retreat is in comparison with the shoreline proxy position surveyed on June 2020 (reference situation before shoreface nourishment). Horizontal black lines refer to groynes and to breakwater.
Figure 5. Time series of offshore significant wave height (a), peak period (b) and mean wave direction (c) obtained from CMEMS (https: / /marine.copernicus.eu/, accessed on 28 June 2021), and 15-day moving average (red). Time-series of the relative 1.05 m (MSL) shoreline proxy advance seawards (warm colors) or retreat landwards (cold colors) (d) along the coastal stretch from Vagueira (0 m) to Barra (9500 m). The relative advance or retreat is in comparison with the shoreline proxy position surveyed on June 2020 (reference situation before shoreface nourishment). Horizontal black lines refer to groynes and to breakwater.
Figure 6. Time series of offshore significant wave height (a), peak period (b) and mean wave direction (c) obtained from CMEMS (https: / /marine.copernicus.eu/, accessed on 28 June 2021), and 15-day moving average (red). Time-series of the relative 1.05 m (MSL) shoreline proxy advance seawards (warm colors) or retreat landwards (cold colors) (d) along the coastal stretch from Vagueira (0 m) to Barra (9500 m). The relative advance or retreat is in comparison with the shoreline proxy position surveyed on the previous survey. Horizontal black lines refer to groynes and to breakwater.
Figure 6. Time series of offshore significant wave height (a), peak period (b) and mean wave direction (c) obtained from CMEMS (https: / /marine.copernicus.eu/, accessed on 28 June 2021), and 15-day moving average (red). Time-series of the relative 1.05 m (MSL) shoreline proxy advance seawards (warm colors) or retreat landwards (cold colors) (d) along the coastal stretch from Vagueira (0 m) to Barra (9500 m). The relative advance or retreat is in comparison with the shoreline proxy position surveyed on the previous survey. Horizontal black lines refer to groynes and to breakwater.
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