International Environmental Modelling and Software Society (iEMSs) 7th Intl. Congress on Env. Modelling and Software, San Diego, CA, USA, Daniel P. Ames, Nigel W.T. Quinn and Andrea E. Rizzoli (Eds.) http://www.iemss.org/society/index.php/iemss-2014-proceedings GIS-based environmental modeling with tangible interaction and dynamic visualization Anna Petrasova a , Brendan Harmon b , Vaclav Petras a and Helena Mitasova a a Department of Marine, Earth, and Atmospheric Sciences, North Carolina State University, Campus Box 8208, Raleigh, North Carolina, USA (akratoc@ncsu.edu, vpetras@ncsu.edu, hmitaso@ncsu.edu) b College of Design, North Carolina State University, Raleigh, North Carolina, USA (baharmon@ncsu.edu) Abstract: We present a new, affordable version of TanGeoMS, a tangible geospatial modeling and visualization system designed for collaboratively exploring how terrain change impacts landscape pro- cesses. It couples a physical, three-dimensional model of a landscape with geospatial modeling and analysis through a cycle of scanning and projection. Multiple users can modify the physical model by hand while it is being scanned; by sculpting the model they generate input for modeling of geophysical processes. The modeling results are then visualized by projecting images or animations back on the physical model. This feedback loop is an intuitive way to evaluate the impacts of different scenarios including anthropogenic and natural landscape change. Integration with GRASS GIS, a free and open source geographic information system, provides TanGeoMS with a variety of easily accessible geospa- tial analysis and modeling tools. To demonstrate the environmental modeling applications of TanGeoMS, we will demonstrate how development can be planned based on feedback from landscape processes such as hydrologic simulation and wildfire modeling with variable fuel distribution. Keywords: tangible user interface; landscape process modeling; visualization; GRASS GIS; Kinect 1 I NTRODUCTION Landscape has a major influence on physical processes such as water flow and sediment transport. It affects, both directly and indirectly, how we make decisions about development, transportation infras- tructure and agriculture. It is, therefore, crucial – not only for scientists, but also for decision-makers who may not have a strong background in the natural sciences – to understand the often unexpected impacts of changes to the landscape. Complex computational models are used to study the impact of landscape change; it can be relatively unintuitive to work with these models because we are separated from our data by multiple layers of abstraction when using a mouse, keyboard and digital display. With tangible user interfaces (TUIs), however, we can directly, haptically interact with a physical representation of dig- ital data. By coupling representation and input, we can more directly, more intuitively interact with our data [Ishii and Ullmer, 1997]. By linking physical models with digital models, TUIs can make environ- mental modeling more intuitive and scientific representations more engaging. A TUI can be used, for example, to couple a physical model of terrain with its digital elevation model (DEM) [Piper et al., 2002; Kreylos, 2013]. The Tangible Geospatial Modeling System [Mitasova et al., 2006; Tateosian et al., 2010] extends the idea of a TUI that links a physical, malleable terrain model with its digital elevation model by integrating a GIS to broaden the capabilities of the system [Ratti et al., 2004]. GIS offers a set of ready-to-use tools for different types of geospatial analyses and simulations, as well as an interface for visualization. Editing a digital elevation model in a GIS or CAD (computer-aided design) program requires specialized skills and can be tedious even for experts. However, by modifying a physical model instead of its digital representation, users can experiment with different scenarios more intuitively and with much greater