Download PDF - COINAtlantic

Using virtual environments to geovisualize the fate of debris disposed of at seaNicholas Benoy & Nick HedleySpatial Interface Research Lab, Department of Geography, Simon Fraser University, Burnaby, V7A 1S6, Canadandb3@sfu.ca, hedley@sfu.caAbstractThis paper describes the development of a 3D virtual environment (VE) to visualize the phenomenon of oceandisposal near Point Grey, British Columbia, Canada. The VE uses Unity3D, a game engine with functional 3Dphysics to provide an interactive, taskable ocean debris visualization sandbox. Users are able to examine the pathdebris takes from its dumping point to the ocean floor while being acted upon by gravity and ocean currents. Theinteractive geovisualization aims to give scientists and concerned citizens a better understanding of the spatial,temporal and dynamic factors influencing debris disposal in three dimensions.IntroductionPrior to the early 1970s, Canadian oceans were widely regarded as a dumping ground for solid waste, such asengine blocks and other garbage destined for landfills (Environment Canada, 2010). International acknowledgementof these practices as detrimental to the health of ocean ecosystems led to the 1972 Convention on the Prevention ofMarine Pollution by Dumping of Wastes and other Matter. Yet marine dumping of various forms has continued.Environment Canada was delegated the task of running a permit system for previously unregulated waste disposalinto the ocean. It is important to note that ocean disposal is only practiced when no other viable land-basedalternative exists. Approved material for disposal at sea includes: sand dredged from river corridors; fish waste fromplants in remote locations; unused ships; and material from rock slides on remote roads along the coast.Visualizing the out-of-sight and out-of-mindCurrently, scientists in Environment Canada's ‘Disposal at Sea’ program do not have the tools to adequatelyvisualize disposal sites in three dimensions. They are currently limited to 2.5-dimensional representations usingArcScene (a popular ‘3D perspective’ geographic information system (GIS) visualization application). The problemsassociated with this are twofold: (1) due to the cost of maintaining an ArcGIS license, not every scientist is able toeasily access spatial information; (2) the software is difficult to use for those without specialized training.Furthermore, Environment Canada relies on external organizations to simulate the fate of materials disposed of atsea. The research described in this paper implements a visualization that reveals the temporal and spatial dynamicsof this normally invisible part of debris disposal at sea. This visualization approach is delivered using an interactive,user-driven application that can be accessed and used by expert and non-expert stakeholders alike. This in turn mayhelp to build consensus about marine dumping and related issues, which continue to be difficult for citizens tounderstand.Debris in the Deep: an interactive debris end-of-life sandbox VEThe Debris in the Deep Unity3D ‘virtual sandbox’ supports interactive 3D physics based geovisualization ofmarine debris dumping scenarios in bathymetric environments. It provides a new form of geovisual debris analysisfor experts and non-experts. Debris simulations can be customized, enabling rapid exploration of scenarios(quantity, material and mass of debris; different dumping patterns). Geovisual analytics features (such as debris pathrendering) enable visual analysis of differential currents’ influence on debris as it sinks. Combined with highresolutionbathymetry data, this system also allows users to view the movement of objects once they reach the oceanfloor. Debris in the Deep is a ‘sandbox virtual environment’ in the sense that it is a topologically three dimensionalvirtual environment in which the user can control and modify the location and configuration of debris and its releasewithin a volumetric 3D physics-capable geovisualization scene with real bathymetric data. The current virtual203