Competing visions? Simulating alternative coastal futures using a GIS- ANN web application Paulo Morgado * , Eduardo Gomes, Nuno Costa Centre of Geographic Studies, Institute of Geography and Spatial Planning of the University of Lisbon, 1600 Lisboa, Portugal article info Article history: Available online xxx Keywords: Scenario building Public participation Coastal urban areas management GIS Artificial neural network Multilayer perceptron Web application abstract In this paper, we demonstrate the use of scenario building in the context of contested land use visions. We examine a small coastal community located 20 kms south of Lisbon. In Almada e Trafaria/Costa da Caparica, competing stakeholders such as central government, local government, environmental NGO's and private companies each have competing development visions for the area. These include the development of recreation and leisure facilities, a container terminal and the re-naturalization of unused land. We illustrate the added value of the GIS-ANN tool in steering negotiations between these different visions and the potential of a scenario building web application as a tool for problem solving. The emergence of user-created GIS-based web content in Planning has transformed passive users and consumers of geospatial information into active contributors to the development of spatial visions of the future. It allows stakeholders to gauge alternative future land uses thus making planning and decision- making processes potentially more transparent and democratic. In this paper, we detail a new method that enhances GIS-web-based public participation. We build on a combination of GIS basic capabilities and the data mining methods of Artificial Neural Networks (ANN), namely Multilayer Perceptron (MLP) packaged in a friendly (GUI) user interface that runs on the Google Earth platform. Users will be able to articulate different spatial development scenarios for a specific area, to conduct sensitivity analyses for various competing scenarios and to explore causal connections between them. © 2014 Elsevier Ltd. All rights reserved. 1. Introduction Coastal areas are fragile systems that interface intense human and physical interactions of a non-linear type and consequently represent a conflict-prone habitat of contrasting interests. Human- environment systems, such as those present in coastal areas, are characterized by heterogeneity, non-linear relationships and hier- archical structures that give rise to difficulties in understanding system behavior in response to exogenous factors (An et al., 2005). The villages of Trafaria and Costa da Caparica, located on the South bank of Tagus River, set the territory boundaries of our case-study area. The location near Lisbon and in the Tagus river mouth, along with the rich natural environment makes this location a competitive area for different investments and therefore, the emergence of conflicting interests. Local and national environ- mental associations would like re-naturalizate the area and adopt environmental protection while the Lisbon Port Authority and central government present financial arguments to support actions for developing a new container terminal in Trafaria that will pro- vide a movement capacity of two million TEU's per year. This underlying rationale of this paper is to provide answers for assuring a balanced organization and management of the coastal area on the one hand and to solve existent land use conflicts and avoid future discord, on the other. This will help policymakers make better and more informed decisions on future development policies. To deal with this complex system, the model we have developed builds on a bottom-up approach as spatially-extended systems are capable of non-trivial collective behavior. Since these kinds of emergent properties cannot be derived from the properties of individual elements alone it is difficult to predict this behavior. Using computer simulation allows for the precise study of the dy- namics which cannot be observed using analytical methods alone (Sim~ oes et al., 2009). We use a GIS based artificial neural networks (ANN) web based application model that allows users with basic GIS skills to simulate alternative coastal land use futures. This way, competing development visions can be compared and the trade- offs between them can be articulated. * Corresponding author. E-mail address: paulo@campus.ul.pt (P. Morgado). Contents lists available at ScienceDirect Ocean & Coastal Management journal homepage: www.elsevier.com/locate/ocecoaman http://dx.doi.org/10.1016/j.ocecoaman.2014.09.022 0964-5691/© 2014 Elsevier Ltd. All rights reserved. Ocean & Coastal Management xxx (2014) 1e10 Please cite this article in press as: Morgado, P., et al., Competing visions? Simulating alternative coastal futures using a GIS-ANN web application, Ocean & Coastal Management (2014), http://dx.doi.org/10.1016/j.ocecoaman.2014.09.022