Ocean Dynamics

, Volume 55, Issue 5–6, pp 416–429 | Cite as

Horizontal patterns of water temperature and salinity in an estuarine tidal channel: Ria de Aveiro

  • Nuno VazEmail author
  • João Miguel Dias
  • Paulo Leitão
  • Inês Martins
Original paper


This work presents results from two complementary and interconnected approaches to study water temperature and salinity patterns in an estuarine tidal channel. This channel is one of the four main branches of the Ria de Aveiro, a shallow lagoon located in the Northwest coast of the Iberian Peninsula. Longitudinal and cross-sectional fields of water temperature and salinity were determined by spatial interpolation of field measurements. A numerical model (Mohid) was used in a 2D depth-integrated mode in order to compute water temperature and salinity patterns. The main purpose of this work was to determine the horizontal patterns of water temperature and salinity in the study area, evaluating the effects of the main forcing factors. The field results were depth-integrated and compared to numerical model results. These results obtained using extreme tidal and river runoff forcing, are also presented. The field results reveal that, when the river flow is weak, the tidal intrusion is the main forcing mechanism, generating saline and thermal fronts which migrate with the neap/spring tidal cycle. When the river flow increases, the influence of the freshwater extends almost as far as the mouth of the lagoon and vertical stratification is established. Results of numerical modelling reveal that the implemented model reproduces quite well the observed horizontal patterns. The model was also used to study the hydrology of the study area under extreme forcing conditions. When the model is forced with a low river flow (1 m3 s−1) the results confirm that the hydrology is tidally dominated. When the model is forced with a high river flow (1,000 m3 s−1) the hydrology is dominated by freshwater, as would be expected in such an area.


Salinity Temperature Transport model Coastal lagoon Ria de Aveiro Espinheiro channel 



The first author of this work has been supported by the University of Aveiro through a PhD grant and by the FACC fund of the Portuguese FCT.


  1. Abbot MB, Damsgaardand A, Rodenhuis GS (1973) System S21, Jupiter, a design system for two-dimensional nearly-horizontal flows. J Hyd Res 1:1–28CrossRefGoogle Scholar
  2. Arakawa A, Lamb V (1977) Computational design of the basic dynamical processes of the UCLA general circulation model. Mon Weather Rev 125:2293–2315Google Scholar
  3. Barnes RSK (1977) The coastline. Wiley, Chichester, UK, p 356Google Scholar
  4. Barnes RSK (1980) Coastal lagoons. Cambridge University press, Cambridge, p 106Google Scholar
  5. Castanho JP, Carvalho R, Vera-Cruz D (1968) Barragem no rio Vouga e desvio dos esgotos–anteprojecto (55 pp), unpublished report, IIGoogle Scholar
  6. Chippada S, Dawson C, Wheeler M (1998) A godonov-type finite volume method for the system of shallow water equations. Comput Methods Appl Mech Eng 151:105–130CrossRefGoogle Scholar
  7. Cressie NAC (1993) Statistics for spatial data–revised edition. John Wiley & Sons, New York, p 900Google Scholar
  8. Dias JM (2001) Contribution to the study of the Ria de Aveiro hydrodynamics. PhD Thesis, University of Aveiro, PortugalGoogle Scholar
  9. Dias JM, Lopes JF, Dekeyser I (1999) Hydrological characterisation of Ria de Aveiro, Portugal, in early summer. Oceanologica Acta 22(5):473–485CrossRefGoogle Scholar
  10. Dias JM, Lopes JF, Dekeyser I (2000) Tidal propagation in Ria de Aveiro lagoon, Portugal. Phys Chem Earth (B) 25:369–374Google Scholar
  11. Dias JM, Lopes JF, Dekeyser I (2001) Lagrangian transport of particles in Ria de Aveiro Lagoon, Portugal, Phys Chem Earth (B) 26(9):721–727Google Scholar
  12. Dias JM, Lopes JF, Dekeyser I (2003) A numerical system to study the transport properties in the Ria de Aveiro lagoon. Ocean Dynamics 53:220–231CrossRefGoogle Scholar
  13. Dias JM, Fernandes, E.H. (2005) Tidal and subtidal propagation in two Atlantic Estuaries: Patos Lagoon (Brazil) and Ria de Aveiro Lagoon (Portugal). J Coastal Res, SI39 (in press)Google Scholar
  14. Dronkers JJ (1964) Tidal computations in rivers and coastal waters. North-Holland Publishing Company, AmsterdamGoogle Scholar
  15. Dyer KR (1997) Estuaries: a physical introduction, 2nd edn. John Wiley & Sons, New York, p 195Google Scholar
  16. Ferziger J, Peric M (1995) Computational methods for fluid dynamics. Springer, New YorkGoogle Scholar
  17. Kjerfve B (1994) Coastal lagoons processes. In: Kjerfve B (ed) Coastal lagoons processes. Elsevier Oceanography Series, Amsterdam, n°60, pp 1–8Google Scholar
  18. Leendertse J (1967) Aspects of a computational model for long water wave propagation, Memorandum RH-5299-RR. Rand Corporation, Santa MonicaGoogle Scholar
  19. Leendertse J, Liu S (1978) A three-dimensional turbulent energy model for non-homogeneous estuaries and coastal sea systems. In: Nihoul J (ed) Hydrodynamics of estuaries and fjords. Elsevier, Amsterdam, pp 378–405Google Scholar
  20. Lopes JF, Dias JM, Dekeyser I (2001) Influence of tides and river inputs on suspended sediment transport in the Ria de Aveiro lagoon, Portugal, Phys. Chem Earth (B) 26(9):729–734Google Scholar
  21. Martins F, Leitão P, Silva A, Neves R (2001) 3D modelling in the Sado estuary using a new generic vertical discretization approach. Oceanologica Acta 24(1):1–12CrossRefGoogle Scholar
  22. Moreira MH, Queiroga H, Machado MM, Cunha MR (1993) Environmental gradients in a southern estuarine system: Ria de Aveiro, Portugal, Implications for soft bottom macrofauna colonization. Neth J Aquat Ecol 27(2–4):465–482CrossRefGoogle Scholar
  23. Pawlowicz R, Beardsley B, Lentz S (2002) Classical tidal harmonic analysis including error estimates in MATLAB using T_TIDE. Computers & Geosciences 28:929–937CrossRefGoogle Scholar
  24. Vaz N, Dias JM, Leitão P (2004) Hydrodynamical modelling of the Ria de Aveiro lagoon: Mohid’s preliminary calibration. Proceedings of Littoral 2004: pp 774–775Google Scholar
  25. Vicente CM (1985) Caracterização hidráulica e aluvionar da Ria de Aveiro, Utilização de modelos hidráulicos no estudo de problemas da Ria, in: Jormadas da Ria de Aveiro, III, Edição da Câmara Municipal de Aveiro, Portugal pp 41–58Google Scholar
  26. Vinokur M (1989) An analysis of finite-difference and finite-volume formulations of conservation laws. J Comput Phys 81:1–52CrossRefGoogle Scholar

Copyright information

© Springer-Verlag 2005

Authors and Affiliations

  • Nuno Vaz
    • 1
    Email author
  • João Miguel Dias
    • 2
  • Paulo Leitão
    • 3
  • Inês Martins
    • 4
  1. 1.Departamento de FísicaUniversidade de Aveiro, Campus de SantiagoAveiroPortugal
  2. 2.Departamento de FísicaUniversidade de Aveiro, Campus de SantiagoAveiroPortugal
  3. 3.HidromodLisboaPortugal
  4. 4.Departamento de FísicaUniversidade de Aveiro, Campus de SantiagoAveiroPortugal

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