Abstract:
The Aveiro coastal area is highly vulnerable to erosion, because
it is constituted primarily by low-lying lands of sandy sediments
that are frequently subjected to severe wave conditions and large
tidal amplitudes (Coelho et al., 2011), as well as due to the close
proximity to the Aveiro lagoon and several urban waterfronts. In
this region the problems associated with coastal erosion are often
reported and discussed (Coelho, 2005; EUrosion, 2006;
Pais-Barbosa et al., 2006; Coelho et al., 2007), constituting a
concern for the local populations and stakeholders. Furthermore,
the retreat of the shoreline may imply the breaching of a new
entrance to the Aveiro lagoon, which would cause major social,
economic and environmental impacts. This breaching has only
been avoided by emergency works which have been carried out
frequently over the past few years. Increased vulnerability is
mainly related to the sedimentary deficit registered in the
Portuguese coast, due to the decrease of incoming sediments from
river sources (Mota-Oliveira, 1997).
Over the years the Esmoriz-Furadouro and Vagueira-Mira
stretches have been affected by flood and erosion processes due to
coastal vulnerability to sea wave’s action (Figure 1). Considering
the expected modifications of the coastal erosion drivers induced
by climate changes, it is important to define their potential effects,
trying to anticipate hydro/morphodynamics changes in coastal
areas, through sea-level rise, increase of storminess and rotations
in the wave regime. It is expected that these phenomena will
increase coastal flooding of low-plains, houses and infrastructures,
causing economic damage and eventual patrimonial, cultural and
ecological losses. This work applies numerical models to predict
shoreline evolution, in a medium-long term perspective,
contributing to establish trends and foresee shoreline position
scenarios.
Two models, GENESIS (U.S. Army Corps of Engineers) and LTC
(Long-Term Configuration), were applied to anticipate the
shoreline position for the year 2100, through the evaluation of four
scenarios in a perspective of the effects of different phenomena
associated with climate change.