MODELLING LONG-TERM SHORELINE EVOLUTION: FIGUEIRA DA FOZ BEACH, PORTUGAL
ICCE 2016 Cover Image
DOC

Keywords

numerical models
longshore sediment transport
accretion rates
jetty
calibration and validation

How to Cite

Pereira, C., Coelho, C., & Silva, P. A. (2017). MODELLING LONG-TERM SHORELINE EVOLUTION: FIGUEIRA DA FOZ BEACH, PORTUGAL. Coastal Engineering Proceedings, 1(35), sediment.17. https://doi.org/10.9753/icce.v35.sediment.17

Abstract

This work applies two different shoreline evolution numerical models (LTC and GENESIS) in two different time periods (1980 2010 and 2010-2014) to compare respectively the calibration and validation performance of the models. The models were applied to evaluate long-term shoreline position and longshore sediments transport evolution, considering as a case study a sandy beach stretch located updrift of the Figueira da Foz harbor jetty, on the Northwest Portuguese coast. Due to the jetty extension, this stretch exhibits a clear accretion trend during the analyzed time periods. For this region, the longshore sediment transport rate estimated by several authors varies between 200 and 1500x103m3/year. According to the modelling results, it was observed that both models reproduce reasonably well the shoreline evolution between 1980 and 2010. In average, the LTC model reproduces a 2010 shoreline position nearest the observed and GENESIS presents better approximation in the Northern part of the beach and also near the South (downdrift) border (just close to the Northern jetty of the harbor). The modeled shoreline average accretion rates for the considered stretch is quite similar and close to the values referred in the bibliography, which indicates that the beach presents 500 meters of maximum accretion width updrift the jetty (about 16.6m/year). In what concerns to the longshore sediment transport it was observed that numerical models generally indicate lower values than the bibliography, being GENESIS results higher and closer to the observed than the LTC. These results are common in the numerical modelling of shoreline evolution, showing that is difficult to simultaneously represent both the shoreline position and sediment transport volumes. After calibration, LTC validation was evaluated for the time period between 2010 and 2014 to allow confidence in the extrapolation of results to the future. Estimated deposition rates of about 350x103m3/year were obtained at the harbor entrance.
https://doi.org/10.9753/icce.v35.sediment.17
DOC

References

Abecasis, F., Matias, M.F., Carvalho, J.J., Vera-Cruz, D. 1962. Methods of determining sand and silt movement along the coast, in estuaries and in maritime rivers. Lab. Nac. Eng. Civil. Technical paper nº 186, Lisboa, 25p.

Agri-Pro. 2004. Estudo de impacte ambiental do projecto das obras de melhoria das condições de abrigo no cais do sector comercial e de manutenção do canal de acesso ao porto da Figueira da Foz, Agri-Pro Ambiente - Estudo Prévio.

Almeida, J.L., Seabra-Santos, F. 1994. Numerical modelling of the "Mareta† wave in Figueira da Foz Port, Seminário Luso-Francês de modelação em hidráulica marítima, Coimbra, Portugal, 103-114.

Baptista, P., Coelho, C., Pereira, C., Bernardes, C., Veloso Gomes, F. 2014. Beach Morphology and Shoreline Evolution: Monitoring and Modeling Medium-Term Responses (Portuguese NW Coast Study Site), Coastal Engineering Journal, Elsevier, 84: 23-37.

Capitão, R.P., Fortes, C.J., Carvalho, M.M. 1997. Coastal dynamic analysis on the stretch Cape Mondego - Mondego Estuary. Erosions at Buarcos. Sea wave study. Report 167/97 NPP, LNEC, Lisboa, 28p.

Coelho, C. 2005. Riscos de Exposição de Frentes Urbanas para Diferentes Intervenções de Defesa Costeira, Ph.D. thesis, Universidade de Aveiro, 404p.

Coelho, C., Veloso-Gomes, F., Silva. R. 2007. Shoreline coastal evolution model: two Portuguese case studies, Proceedings of the 30th International Conference, 3430-3771.

Coelho, C., Silva, R., Veloso-Gomes, F., Taveira-Pinto, F. 2009. Potential Impacts of Climate Change on NW Portuguese Coastal Zones, ICES Journal of Marine Science, 66: 1497-1507.

Coelho, C., Lima, M., Veloso-Gomes, F. 2013. Relationship between cross-shore active profile and one-line shoreline evolution models performance, Journal of Coastal Research, SI65, 2107-2112.

Cunha, P.P., Dinis, J. 1998. Beach erosion between cabo Mondego and Figueira da Foz (Portugal Midwest), from 1995 to 1998. Territorium, 5, 31-50.

Dias, J.A., Ferreira, O., Pereira, A.R. 1994. Estudo sintético de diagnóstico da geomorfologia e da dinâmica sedimentar dos troços costeiros entre Espinho e Nazaré. Edição eletrónica de 2005: w3.ualg.pt/~jdias/JAD/ebooks.

Dodet, G., Bertin, X., Taborda, R. 2010. Wave climate variability in the North-East Atlantic Ocean over the last six decades. Ocean Modeling, 31 (3-4), 120-131.

Ferreira, Ó. 1993. Caracterização dos principais fatores condicionantes do balanço sedimentar e da evolução da linha de costa entre Aveiro e o Cabo Mondego. Master thesis, Universidade de Lisboa, 166p.

Freire, P., Oliveira, F.S.B.F., Capitão, R., Fortes, C., Costa, M. 2004. Cross-shore Evolution of Buarcos Beach, Portugal. Proc. 29th International Conference on Coastal Engineering, ASCE, Vol. 3: 2314-2326.

Hallermeier, R.J. 1978. Uses for a calculated limit depth to beach erosion. Proceedings 16th Coastal Engineering Conference, American Society of Civil Engineers, 1493- 15 12.

Hanson, H., Kraus, N.C. 1991. GENESIS - Generalized model for simulating shoreline change, Vol. 2: Reference Manual and Users Guide, US Army Corps of Engineers. 431p.

Larangeiro, S.H.C.D., Oliveira, F.S.B.F., Freire, P.M.S., 2003. Longshore sediment transport along a sandy coast with hard rock outcrops. Shore & beach, Vol. 71, N. 2, 20-24.

Oliveira, F.S.B.F., Freire, P.M.S., Larangeiro, S.H.C.D. 2002. Characterisation of the dynamics of Figueira da foz beach, Portugal. Journal of Coastal Research, 563 (36), 552-563.

Pereira, C., Coelho, C., Ribeiro, N., Fortunato, A., Lopes, C., Dias, J. 2013. Numerical Modelling of Shoreline Evolution in the Aveiro Coast, Portugal - Climate Change Scenarios, Journal of Coastal Research, SI65, 2161-2166.

Ribeiro, N.A., Fortunato, A.B., Rocha, A.C. 2012. Efeito das alterações climáticas no regime de agitação marítima no Atlântico Norte e costa portuguesa, 2as Jornadas de Engenharia Hidrográfica, 163-166.

Roebeling, P., Coelho C., Reis, E. 2011. Coastal erosion and coastal defense interventions - cost/benefit analysis, Journal of Coastal Research, SI64, 1415-1419.

Silva, R., Coelho, C., Taveira-Pinto, F., Veloso-Gomes, F. 2007. Dynamical Numerical Simulation of Medium Term Coastal Evolution of the West Coast of Portugal, Journal of Coastal Research, SI50, 263-267.

Silva, R., Veloso-Gomes, F., Taveira-Pinto, F., Coelho, C. 2011. 3D Movable Bed Model Results Integration in Shoreline Evolution Model, Coastal Sediments '11, Miami, Florida, USA. World Scientific Publishing.

Vicente, C.M., Clímaco, M. 2003. Evolução de linhas de costa. Desenvolvimento e aplicação de um modelo numérico; Informação Técnica Hidráulica ITH 42, Laboratório Nacional de Engenharia Civil, Lisboa, 167p.

Authors retain copyright and grant the Proceedings right of first publication with the work simultaneously licensed under a Creative Commons Attribution License that allows others to share the work with an acknowledgement of the work's authorship and initial publication in this Proceedings.