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SAR analysis, data mining & GIS mapping of the Central Mediterranean to document the violations of migrants’ rights & deaths at sea

Summer 2013 report of GISCorps’s contribution to Forensic Oceanography

By: Charles Heller and Lorenzo Pezzani, Centre for Research Architecture, Goldsmiths, University of London, Situ Studio, New York & GISCorps Volunteers: Rossana Padeletti, Donald Ferguson, David Metzler, & Said Abou Kharroub


Forensic Oceanography (FO) is a project led by Charles Heller and Lorenzo Pezzani as part of the European Research Council project “Forensic Architecture” directed by Centre for Research Architecture, Goldsmiths, University of London ( It aims to use geospatial technology to document the violations of migrants’ rights and deaths at sea. GISCorps volunteers continued to contribute this summer to the analysis of SAR imagery and AIS vessel tracking data towards a legal case aiming to determine responsibility for the death of 63 migrants of the Libyan coast in 2011. GISCorps volunteers also contributed to data mining and GIS mapping towards the new version of WatchTheMed (, a participatory mapping platform aiming to monitor the Mediterranean so as to document violations and prevent them from occurring.

Deaths at the Borders of Europe. Olivier Clochard and Nicolas Lambert (Migreurop), Atlas des migrants en Europe (Paris: Armand Colin, 2013).

In summer of 2013, GISCorps volunteers have continued to support the Forensic Oceanography (FO) research project led by Charles Heller and Lorenzo Pezzani as part of the European Research Council project “Forensic Architecture” directed by Centre for Research Architecture, Goldsmiths, University of London ( The project aims to draw accountability to the deaths of migrants at the maritime borders of the EU – of which over 14.000 cases have been documented by the press over the last 20 years.

In particular, GISCorps continued to support an investigation into the “Left-to-die boat” case, which cost the life of 63 migrants of the Libyan coast in 2011, through SAR imagery and AIS vessel tracking data analysis. GISCorps volunteers also contributed to data mining and GIS mapping towards the new version of WatchTheMed (, a participatory mapping platform aiming to monitor the Mediterranean so as to document violations and prevent them from occurring.

Chain of events of the Left-to-die boat case
A) Departure point at Port of Tripoli between 00:00 and 02:00 UTC on 27 March. Boat first spotted by a French aircraft at 14:55 GMT on 27 March at position LAT 33°40’ N, – LON 13°05′ E
(B) GPS location of vessel at 16:52 GMT on 27 March 2011 at position LAT 33 58.2 N – LON 12 55.8 E as determined by the MRCC based on locations established by the satellite phone provider Thuraya.
(C) The GPS position of the boat was determined a second time (at 19:08 GMT on 27 March at position LAT 34 07.11 N – LON 12 53.24 E, again based on information provided by Thuraya.
(D) The vessel began to drift within a 4.3 nm radius of position 34 24.792 N – 12 48.576 E at approximately 07:00 GMT on 28 March.
E) Between 3 and 5 April the migrants encounter a military ship. On 10 April the boat lands

1st initiative: The “Left-to-die boat” case

In the case of what is now referred to as the “Left-to-die boat”, 72 migrants fleeing Tripoli by boat on the early morning of March 27 2011 ran out of fuel and were left to drift for 14 days until they landed back on the Libyan coast. With no water or food on-board, only nine of the migrants survived. In several interviews, these survivors recounted the various points of contacts they had with the external world during this ordeal. This included describing the aircraft that flew over them, the distress call they sent out via satellite telephone and their visual sightings of a military helicopter which provided a few packets of biscuits and bottles of water and a military ship which failed to provide any assistance whatsoever. The events, as recounted by these survivors, appeared to constitute a severe violation of the legal obligation to provide assistance to any person in distress at sea, an obligation sanctioned by several international conventions.
In response to this incident, a coalition of NGOs was formed (constituted primarily by GISTI (, FIDH ( and Migreurop (, Human Rights Watch ( to seek accountability for the non-assistance of migrants at sea during and in the aftermath of Arab Spring in general and in the case of the “left-to-die boat” in particular. The Forensic Oceanography project offered its expertise in spatial analysis to this initiative and published a report on 11 April 2012, which was the basis for a first case filed against the French military. The report included the analysis of SAR imagery analysis aiming to identify vessels in vicinity to the rifting boat produced by GISCorps volunteer Lawrence Fox III, Humboldt State University Emeritus Professor of Remote Sensing and Consultant:

More information on this initiative can be found here:

SAR image analysis by Rossana Padeletti, indicating vessel returns in vicinity of migrant boat
New SAR imagery analysis for Left-to-die boat case
While we had previously relied on Envisat SAR data of 75m resolution, we were able to acquire Radarsat-1 data of 50m resolution and concerning a key moment in the chain of events: the 4th of April 2011. This was the day when, according to our reconstruction based on several sources of evidence, the migrants’ boat at drift since already 8 days encountered a still unidentified military vessel. At this point in the chain of events, almost half of the 72 people had already died. Despite witnessing the distress of the migrants – the vessel came up to 10m and members of the crew onboard took photographs of the migrants – the military vessel provided no assistance whatsoever, effectively letting the migrants die in all knowledge of their tragic fate.
GISCorps volunteer Rossana Padeletti, GIS and Remote Sensing Specialist and consultant, completed the analysis of the 04.2011 image that was submitted as additional evidence for the “left-to-die boat” case and presented at a press conference held by a coalition of migrants’ rights NGOs in Paris on the 18th of June 2013. Her analysis demonstrates that there was considerable presence of vessels in the area surrounding the drifting migrants’ vessel on the probable day of this deadly encounter.
AIS vessel tracking data analysis by Donald H. Ferguson, attempting to corroborate SAR image returns with AIS tracks
Tentative AIS data analysis for Left-to-die boat case
We further attempted to combine the SAR analysis of vessel returns with AIS vessel tracking data, so as to be able to identify the commercial vessels in the area and thus determine probable military vessels as the unaccounted for returns. Donald H. Ferguson, Geospatial Analyst and GISCorps volunteer, provided a thorough and important analysis of the acquired coastal and satellite AIS data, but due to insufficient coverage of coastal AIS stations of the Southern coast of the Central Mediterranean and infrequent satellite AIS data availability during the time of events, the analysis was not conclusive. While some vessels were identified, it did not allow to provide the overall image thought for. The analysis did none the less provide elements of understanding that may be used in the legal case subsequently, and no less importantly allowed us to develop a better understanding of the maritime traffic monitoring technologies in the area – and their limits.  mapping platform with key layers

2nd initiative: WatchTheMed

In July 2012, in the frame of the Boats4Peope campaign (, FO launched the pilot phase of an online participatory mapping platform called WatchTheMed (WTM, pilot available at The aim here was to make the mapping tools used towards the “Left-to-die boat” case described above available to the wider movement, so that they could be used towards more cases and increase accountability at sea. By combining new tools for documentation and specializing violations at sea with the tools of “crowdsourcing” used in crisis mapping so as to come closer to a documentation in real time and in a participatory mode, our hope was not only to document violations occurring in the past but to tend towards the real time so as to actually prevent violations and death from occurring. The pilot phase of WTM which was deemed successful saw the contribution of two GISCorps volunteers Steve Etherington and Keith McCrary to produce the layers for the online map.
In July 2013, we thus launched the permanent version of the WTM platform, which involved customizing the Ushahidi platform and continuing to develop the WTM layers, so as to provide the most complete picture of maritime life in relation to migration: different actors and technologies aiming to control migrants, but also jurisdictions as well as other actors who populate the sea and encounter migrants. David Metzler, GIS Technician recruited by GISCorps, updated our Search and Rescue zone and GSM coverage layers. Additional data mining was provided by Said Abou Kharroub and Donald H. Ferguson. Because information on the maritime environment is both difficult to access and continuously evolving, we hope GISCorps volunteers will continue to join us and shape what is ultimately a “tool in progress”.
WTM post on “rescued” migrants brought back to Libya:
Since it was re-launched in July 2013, WTM has contributed to save lives – in several instances we received information of ongoing situations of distress and, by contributing to localize the boats, we could support families and NGOs to contact the relevant rescue authorities. WTM also has been instrumental in documenting continuing violations at sea and new patterns of migration control. In particular, several incidents this summer have involved commercial vessels being called to “rescue” migrants outside of EU costal states’ Search and Rescue zones (in red), with the aim of making Non-EU southern states responsible for taking them back. This is particularly problematic in instances (as that indicated above) where migrants are brought back to Libya, a country which is not signatory of the Geneva Convention on refugees and in which violations of migrants rights are recurrent. Because large commercial vessels are required to carry AIS transponders and AIS data is available live online, we were able to document these trajectories and in some cases NGOs used this data to pressure authorities into allowing the vessels to disembark the migrants on EU territory.
WTM will continue to operate and gather momentum in the months to come, and we hope in the future to constitute a group of GISCorps volunteers who can support the project on a rotating basis, to further develop layers or support the investigation into cases through GIS analysis. With GISCorps help, we aim to develop WTM into an effective warning and documentation mechanism for violations and situations of distress at sea.
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