Juerg Lichtenegger 
  
2 REQUIREMENTS OF THE COAST GUARDS 
Within the Mediterranean region the approach of the different countries to survey their proper territorial 
waters or even the open sea area can be described as widely divers. It ranges from intentions and plans to 
fully operational procedures. The level of service development and equipment in use is accordingly. The 
range is between apparent total absence of means for monitoring and for intervention up to a well 
structured organisation with a variety of equipment to survey and also to combat, analyse and treat 
polluting substances. 
It has to be admitted that collecting such information in the countries around the Mediterranean is not a 
straightforward task and also subject of politics and confidentiality. It is assumed that in the southern and 
eastern part of the region, much more procedure and equipment are in place, but due to its connection to 
the military, relevant information can not be accessed. At various conferences within the region, the 
practical aspects of combating oil pollution is seldom treated since discussions include more general 
statements and good intentions than procedures and their enforcement. However, ESA/ESRIN as a 
promoter for the use of ERS-SAR data took the initiative to convene operational entities on various 
occasions to discuss the topic (G.Calabresi Ed., 1996). 
Today only Italy, France and Spain have developed and established an organisation that would allow an 
efficient monitoring of their national coastal area. All these countries have available a park of aircraft or 
helicopters for monitoring and immediate intervention as well as a fleet of ships for clean-up operations. 
They have developed well structured and functional entities of staff operating around the clock. However 
only France performs regular patrolling flights, while in general, the other two countries intervene only 
upon requests or messages of sightings of oil slicks in the vicinity of the coast. 
The interest of these operational entities towards satellite remote sensing can be judge as to be 
ambiguous. On the one hand the advantage of the much enlarged observation zone in time and space has 
been recognized, as well as the quality in terms of reliability to correctly identify oil slicks from satellite 
data. On the other, the many unknown factor such the impact of high technology, the worry of 
substituting aircraft operations by satellites but also the complexity of joint operations produce a rather 
strong hesitation in accepting a new approach. 
An often expressed requirement of coast guards regards data availability. Frequencies requested range 
from hourly coverage to at least one scene per day. Today’s systems are far from offering this. Only after 
the launch of ENVISAT and by joining the acquisitions with RADARSAT, a nearly daily coverage of the 
Mediterranean can be achieved. A further obstacle is the pricing policy of the satellite data. Current prices 
are mostly based on single frames, which are hardly acceptable for a regular monitoring service. What 
needs to be achieved is an accounting for a surface/time based monitoring, which financially is not only 
supported by the entity responsible but also by one or several countries of the region. However most of 
responsible entities for oil pollution do not foresee expenses arising from purchasing satellite data, 
therefore a change in budget preparation is needed as well. 
In discussions with the coast guards, the concept of random coverage in time and space is difficult to 
accept, even when planned well ahead in time. Buttaking into account the availability of aircraft or fast 
ships, (which is the case in most countries in the Mediterranean) and near-real time satellite products 
would already allow a wide coverage of active monitoring. 
Experiences made with the Italian Coast guard confirm this approach. By regulations this institution is 
obliged to check any incoming report regarding oil pollution. During a test-phase using ERS SAR images 
they received oil spill sightings a few hours after acquisition of the data. Whenever an aircraft or ship was 
available for reaching the spill out in the sea, a sortie was programmed. In practical all cases the reported 
spill could be confirmed. However this encouraging result had also the disadvantage that since there are 
very many slicks of considerable size, too often verifications needed to be made. In order to use satellite 
data in a cost-effective way a new procedure needs to be worked out. It could include that an intervention 
by the coast guard is necessary only in the following two cases: 
- an observed spill can potentially pollute a coast (close monitoring and eventual clean-up operation) or 
- a ship in action of spilling is observed (identification of the ship for legal procecution). 
  
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International Archives of Photogrammetry and Remote Sensing. Vol. XXXIII, Part Bl. Amsterdam 2000.