Wednesday, August 22, 2018

Enhanced maritime situational awareness with Satellite AIS

From GeoSpatialWorld by Guy Thomas

GPS is the only other system that even comes close to the impact of S-AIS in last 150 plus years, but while GPS allowed for mariners to navigate with more surety, it left the maritime world opaque.
S-AIS is quickly making it much more transparent.

Satellite AIS (S-AIS) has created the largest paradigm shift in the maritime world since the steam engine and the screw propeller. (Yes, even larger than GPS!)
The first six satellite constellation was launched by ORBCOMM for the US Coast Guard in 2008 to allow the United States to understand who was approaching its coasts and ports but has since become an ubiquitous tool for an ever-increasing array of maritime applications.

It is also routinely paired with imaging space systems such as electro-optical satellites and, especially synthetic aperture radar (SAR) satellites which can image the Earth day and night, rain or shine.
There are not enough SARsats yet to do this 24/7 but with the increasing number of imaging satellites of all types, SAR, EO and video, it is only a matter of a very few years before nearly every place on Earth will be under near continuous observation/surveillance.
With all three types of imaging satellites there is a natural synergism in the maritime world.
S-AIS gives them the added ability to identify the ships imaged, and if they are not identifiable, the very lack of an identity, or the attempt to hide their identity via spoofing, which is actually counterproductive for the spoofers as they are actually calling attention to themselves by the very act of sending out false information, can lead to further examination by other terrestrial assets such as aircraft and military or law enforcement vessels.

Highlighting the various applications of exactEarth's vessel data services

Many have the mistaken impression that S-AIS is easy to spoof undetected.
Since the very first ORBCOMM satellites with S-AIS as a secondary payload were launched in 2008 there has existed the capability to geo-locate all AIS emitters collected.
That geo-location is compared with the reported position contained in the transmission itself and if it is more than a certain number of miles away the report is flagged and that emitter is collected at every opportunity.
Normally once a position is verified to be “true” all subsequent collection of that emitter by that satellite during that collection opportunity, is discarded.
(A collection opportunity is defined by the time the AIS sensor on the satellite comes into view of the terrestrial transmitter, until it leaves that field of view.)

Also, there are now a number of software tools that process AIS data for a number of uses.
This data includes the Maritime Mobile Service Identity (MMSI The MMSI is a unique 9 digit number that is assigned to each AIS unit.
Some of these software tools contain data bases that strive to record the MMSI of every AIS signal detected anywhere, stretching back to early 2001.
It is very easy for theses software tools to sort through the history of almost every MMSI ever broadcast in milliseconds and detect whether there is something amiss.
Those transmitters are also flagged for special attention.
False locations and false MMSI generates very special attention in some circles.

While GPS allowed for mariners to navigate with more surety, it left the maritime world opaque.
S-AIS is quickly making it much more transparent.
Like GPS, which was created to improve the accuracy of the US’s submarine launched ballistic missiles, S-AIS is rapidly becoming ever more present in the marine world as more and more applications for its data are being discovered and developed.
However, while GPS is now found in many applications for all three environments, sea, air and land, S-AIS’s impact is focused on the marine world where it is causing a major change in its global operations.
It is interesting to note that both satellite navigation and S-AIS were invented at Johns Hopkins University’s Applied Physics Lab.

While S-AIS was created as a maritime security system its usage has expanded into a number of fields.

AIS fishing vessels in the UK
courtesy of Alasdair Rae


The tracking of all the world’s commodities location and the estimate of their time of arrival at destination is now down to a very few hours.
This detailed information, derived from S-AIS and brokers’ records, has allowed commodities traders to be dramatically more accurate in predicting daily prices in many ports of the world, thereby allowing the first few who developed and employed the analysis based on this information to reap huge rewards.

Marine maintenance

Determining when hull and machinery maintenance needs to be scheduled for maximum return on investment because S-AIS allows for very accurate record-keeping of hours of operation – at what loading/speed and in what type of marine environment at what average speed.
These factors are critical to hull maintenance.

Illegal fishing

Determining when a ship which is bound for an area might pose a threat, such as illegal fishing, or having traversed an area known to contaminated with a sea life threatening biological problem such as a diseases.
This allows for the concerned authorities to demand the diversion of the threat bearing vessel.
Also, the pattern of the courses used by fishing boats while fishing are very distinct in many instances.
Several software tools now automatically recognize these patterns.


Using synthetic aperture radar satellites detecting illegal bilge dumping in controlled waters is now much more effective because the exact identification of the offending vessel and its next port of call can often be determined via S-AIS.
When the offending vessel docks, the local authorities can demand to see both its bilges and its log.
If the bilges are clean but there is no log entry as to when they were last pumped clean then a citation, often worth many thousands of dollars, is issued.
The Italian Navy reports this has caused a dramatic reduction in the illegal dumping of bilge waste in the Mediterranean.

Search and rescue

S-AIS has also dramatically improved safety of life at sea by allowing for the location of all ships in an area to be known by all interested parties thereby permitting the speedy reaction to maritime disasters, large and small.
Indeed, AIS transmitters are now being installed on life jackets to assist in recovery of crew in the water.
S-AIS allows for the closest vessels to a maritime problem to be identified and vectored to the site as needed.

Disaster support

It is also a major tool in disaster recovery operations.
In Hatti, S-AIS provided the knowledge of when needed supplies would arrive at ports which were severely damaged and thus had very limited offload capabilities.
S-AIS allowed for the accurate planning of the landing of the most needed supplies in priority order.
It has been used in a similar fashion in many disasters since, in several countries such as the Philippines, which has been hit several times recently with hurricanes, and in the Indian Ocean, Japan and Chile, where tsunamis have severally damaged ports and seacoasts.

Security and Surveillance

Finally, S-AIS is being used worldwide as a primary adjunct to maritime security operations by allowing for the study of normal “pattern of life” operations to determine when anomalous activity is happening.
Thus, surveillance and intercept units can be dispatched with much improved chances of apprehending wrong doers, be smugglers of all types, or illegal fishers, or whatever.
This saves wear and tear on equipment and personnel, as well as money by limiting operating time of scarce assets.
It also raises crew moral because it knows they have a better chance for a productive operation.
And more

The list just keeps getting longer, but clearly, S-AIS is making a huge impact on the maritime world.

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