Environmental sensitivity maps (ESM) of the coastline as part of contingency plans for oil spills has been developed since the late 70’s. First examples of ESM were in Alaska, U.S. (Lower Cook Inlet), thereafter the degrees of sensitivity have been reviewed and improved with the intention to characterize the widest possible range of types of coasts.
Since the late 80’s ESM are done using digital map databases (Geographic Information Systems (GIS)), thereby enabling the automatic generation of sensitivity maps. The NOAA (National Oceanic and Atmospheric Administration, U.S. Department of Commerce) has led standardization developing methodological guidelines (NOAA, 2002) and the automatic production of maps concerning the sensitivity of the coastline faced to a possible oil spill.
The main aim of the ESM of the coastline is the determination of the behaviour of the materials constituting the coastline faced to pollution caused by oil and / or pollutants in similar in nature or behaviour. The determination of the Environmental Sensitivity of the shoreline constitutes a decision support tool, because knowledge of the behaviour of materials in front a spill will establish accurate procedures for each type of coast.
Shoreline classification tasks have been made in a GIS environment, allowing agile handling of the information and benefit management tasks and decisionmaking (reducing response time) during emergencies caused by marine pollution. Incorporating information into a GIS environment allows quick query to the digital databases associated with maps. The advantages of GIS for the elaboration of ESM of the shoreline are: 1) real time knowledge of the types of shoreline affected or potentially affected by pollution, 2) length of shoreline affected, 3) knowledge of the type of environmental protection of the shoreline if any, 4) agile knowledge of the main characteristics of the infrastructure and equipment that will assist cleaning tasks (eg existence of port cranes, first-aid station, dock areas, fresh water, etc..), 5) ability to simplify the types of shoreline, quickly and promptly, if necessary (among others) and 6) facilitate the exchange of information and exposure on the web (internet: web Map Services, SACOSTA ).
The determination of Environmental Sensitivity of the coastline of the Balearic Islands began in 2004 in the Interdisciplinary Oceanography Group (now called TMOOS) of the IMEDEA (Instituto Mediterráneo de Estudios Avanzados; Mediterranean Institute for Advanced Studies) and whose works were updated and continued in the SIAS Division (Division of Strategic Issues and Applications for Society) of SOCIB. The location of the Balearic Islands in the center of western Mediterranean, over 1,500 km of coastline, a population of about one million inhabitants, its ecological richness and uniqueness of its shorelines and an economy based in tourism, justify the need to develop tasks and studies related to the sensitivity of the shoreline.