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Integrated approach for generating maps of environmental vulnerability tooil: case study at Santos Basin, BrazilÁgata Fernandes Romero, Roberto Fioravanti Carelli Fontes & Denis Moledo de Souza AbessaNúcleo de Estudos sobre Poluição e Ecotoxicologia Aquática, UNESP Campus Experimental do Litoral Paulista, São Vicente,11330-900, Brasilagatafr@gmail.com, rcfontes@clp.unesp.br, dmabessa@clp.unesp.brAbstractThe risks of oil spills on coastal and marine environments have increased due to the growth of maritime transportand oil exploration. Actions to prevent or mitigate the effects produced by oil accidents are part of the strategicplanning of oil structures. Maps of environmental vulnerability have been used to plan, and direct actions to combatoil pollution. This investigation proposes the creation of indices for environmental vulnerability to oil, aiming toobtain information on vulnerability which is more accessible and comprehensible. To achieve this, environmentalvulnerability maps were generated, integrating information on environmental sensitivity to oil, coastline vulnerabilityand modeling results for the oil plume fate. Such maps allow a rapid interpretation on the vulnerability of themapped region, also improving the planning process and the responses displayed after an oil spill episode. Theseresults highlight the importance of improving the approaches used to map the environmental vulnerability to oil.IntroductionAs the global maritime trade increases at positive growth rates, the volume of transported cargo has also increasedfrom 8.4 billion tons in 2010 to almost 9 billion tons in 2011 (UNCTAD, 2011). The world fleet grew by 37per cent in just four years (2008 – 2012), and an annual growth of almost 10 per cent in January 2012. In early 2012,the global fleet was 104,305 commercial vessels (UNCTAD, 2012).The intensification of ship traffic may increasethe risks of oil spills related to accidents caused by collisions and groundings. A unique accident involving a tankermay cause catastrophic damages. An example of that is the Exxon Valdez accident, in 1989, which released about36,000 tons of crude oil along the Alaska coast, affecting 1,500 km of coastline (Van de Wiel and Van Dorp, 2011).Large oil spills involving exploration platforms may occur as well, producing large scale environmental impacts. InApril 2010, in the Gulf of Mexico, the explosion of Deepwater Horizon platform caused the spill of about 5 millionbarrels of oil (Ramseur, 2010).It is impossible to predict when accidents will occur. Thus, response actions to oil emergencies must be carefullyplanned, in order to minimize the impacts caused by oil pollution to the marine and coastal environments. In thissense, the maps of environmental vulnerability to oil represent a valuable tool for the planning of response actions inthe case of oil spills as they present information on the sensitivity and susceptibility of mapped areas. Sites with highsensitivity and high probability of oil spill impacts are more vulnerable than those with low sensitivity and lowprobability of oil spill impacts.MethodsThe approach for the creation of vulnerability maps integrates different tools for planning response actionsagainst oil spills, as sensitivity indexes of coastline (ESI Maps) and numerical modeling of oil spill plumes. Suchtools may be integrated, allowing the establishment of different categories of environmental vulnerability to oil, andthus allowing the generation of maps of environmental vulnerability to oil.The method used to create the ESI Maps followed that described by NOAA (2002), which was adapted by theBrazilian Ministry of Environment (Brasil, 2004) with modifications proposed by Romero et al. (2010). The hydrodynamicmodel for the oil plume was produced by Romero et al. (2011), by the use of Spill Impact Model ApplicationPackage – SIMAP (French-McCay, 2004). This model was run in probabilistic mode, for a period of 30 days,45