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11 th International Symposium for GIS and Computer Cartography for Coastal Zones ManagementRia de Aveiro case studyThe littoral of Ria de Aveiro is considered a flood-prone urban region due to its topographical and morphologicalfeatures, characterized by low-lying lands marginal with reduced topography. Ria de Aveiro is a shallow coastallagoon connected to the Atlantic Ocean through a single inlet and is located in the central coastal zone of Portugal.Ria has 158,740 inhabitants (INE, 2011) in the adjoining parishes and plays an important role in the culture andeconomy of the region. Its dynamics are essentially forced by sea level changes at the mouth (essentially induced bytidal forcing, but also dependent on storm surges generated offshore and on sea level rise) and by the freshwaterdischarges of six rivers discharging at main channel’s head. The tide is mesotidal and semidiurnal, and its amplitudeat the inlet ranges from a minimum value of 0.6 m in neap tide to a maximum of 3.2 m in spring tide with an averagevalue of 2 m (Dias et al., 2000). The maximum and minimum water levels are 3.5 and 0.3 m, revealing the importanceof the fortnight cycle in the lagoon dynamics. According to Vargas (2012), the Vouga river has the largestfreshwater contribution, about 77% of the total, with an average annual mean flow of 47.98 m 3 /s, followed by theMira ditches and the Antuã river with a contribution of about 8 m 3 /s and 2.7 m 3 /s, respectively; the Caster/Gondeand Boco rivers give a smaller contribution of about 2.5 m 3 /s and 2 m 3 /s, respectively.Climate scenariosIn the scope of ADAPTARia research project, nine flood extent maps of Ria de Aveiro for different climate scenarioswere produced (see Table 1). The flood-prone areas in Ria de Aveiro were predicted using the ELCIRC hydrodynamicmodel forced by characteristic tides of different ranges (medium, spring and equinoctial) and by takinginto account the local changes in the mean sea level rise. These were predicted for the period 2091–2100 relative to1980–1999, for different SRES scenarios developed by the IPCC (2007), considering the A2 storyline and the uncertainlyresulting from using different GCM (Lopes et al., 2011). Values for different return periods (2, 10 and 100years) of fluvial discharges determined using the SWAT model for present and future scenarios (2100, A2 storyline)for the six rivers discharging in the lagoon and of storm surges (that were found to keep their local characteristicsunchanged in climate change scenarios) were also considered as model inputs. Simulations were performed for thenine climate scenarios and the maximum flooded areas in the model grid were identified, and compared with thereference situation (model forced only by the tide of medium tidal range).Table 1. Climate scenarios.Tidal Fluvial discharge Storm surge Mean sea levelPresent Future PresentMedium Spring EquinoctialPresent 0.42m 0.64m2 10 100 2 10 100 2 10 1001 2 3 4 5 6 7 8 9 Visualization toolsOne step of the ADAPTARia research project focuses on stakeholders and community involvement. Several participatorymethods can be used in order to integrate diverse types of knowledge systems in environmental management,and thus contribute to assimilating multiple perspectives and promoting adaptability in decision-making (e.g.,Gray et al., 2011; Gray et al., 2012). The goal of this research is similar to the study of Gray et al. (2011) – to usevisualisation tools and scenarios to encourage dialogue between scientists, stakeholders and end-users – but with adifferent approach – instead of participatory fuzzy cognitive mapping we use thematic maps and present alternativemanagement scenarios. Therefore, several workshops with the interested parties are planned in order to promoteknowledge exchange, build capacity and formulate/agree on measures to adapt and reduce the risk of flood damagein Ria de Aveiro. As previously mentioned, flood extent for different climate scenarios were provided. By combin-67