This series of blogs and articles will share what we and our partner Maerospace have learned about the realities of global AIS and Satellite-AIS (which will refer to as simply AIS from here on). Over the past decade, Maerospace has worked with every satellite AIS supplier and with users and analysts from around the world. In our work to provide a vastly improved maritime domain awareness data feed using advanced analytics, we have developed a deep understanding of what really goes on in the complex global network of sensors that support AIS. Our goal in this series is to share what we have learned in hopes that this incredibly valuable resource can continue to be enhanced. With the proper understanding of the system, this unique global resource can be a critical tool to help save lives, guard the borders, protect the environment and enhance trade.
Uses of AIS Data
Satellite AIS, combined with Coastal AIS data provides analysts with the ability to track ships globally or within any Area of Interest (AoI).
Many uses of S-AIS have emerged over time. Table 1 shows a summary of the major uses of ship tacking data today.
One key issue is, for each application, to understand the importance of accuracy and timeliness of the data. For many applications, it matters whether the position information and the decision support data derived from positions is correct at the time that decisions are made.
When using AIS or S-AIS, users are rarely interested in all ships everywhere. Instead, there are AREAS of INTEREST (AoI’s) and Vessels of Interest (VoI’s). We suggest that there are also Time’s of Interest (ToI) that must be considered. As we have discussed elsewhere, with Satellite AIS, ships are detected intermittently, regardless of the number of satellites involved. Intermittent detection occurs even with coastal AIS networks whenever ships are beyond about 30 miles from the base station. This means that the AIS data about a ship is always old and often obsolete.
If you are involved in any of the applications shown in Table 1 – Use Cases, then it is essential for you to understand the realities of the age of the data you are using for decision making. Most data suppliers will provide an ability to see the time of the detection being presented. It is always included in data streams and API data access, but map presentations often require the user to click on a ship to display the age of the message, and it is often displayed at the bottom of a long list of meta-data about the ship.
Table 1 – Use Cases
Time Synchronization is Critical
For many applications, users must also predict the position of the vessel into the future, to estimate the estimated time of arrival (ETA) or to plan to meet the vessel at a particular time. For these uses, a thorough understanding of the time factors is essential. To maximize the value of AIS and S-AIS data, training for all analysts about how to interpret the data being presented is essential.
An analyst will sometimes misread a map that appears to show ship positions in an area and may make expensive decisions based on data presented. For this reason, analytics can make a huge difference by removing the need for the analyst to make manual calculations.
Maerospace, TimeCaster™ technology provides a time-synchronized set of ship positions in any area. Using patent-pending machine learning algorithms, it provides an API or web view via data stream. This approach has been proven to provide a global accuracy of fifteen times (15X) improvement over use of raw S-AIS and Coastal data. Time-synchronized positions for all ships can be provided on a NowCast® basis (as of “now” and then the ship positions are updated every 10 minutes) or for the future for any set of ships or area of interest. FutureCast™ capabilities can provide this time-synchronized view for many hours or days into the future. In all cases, the analyst has access to the original AIS data as well as the forecasts.
Monitoring and Alerting
Decision making is about making things happen in the future. Whenever a decision is needed to support any of the use cases in Table 1, the user must assess where the ship will be when the decision comes into play, whether it is planning to receive cargo, interdict a vessel, direct a vessel to a new port, or predict commodity prices based on short-term flows.
When the position predictions are done manually, the process becomes slow and subject to errors. With an automated monitoring and alerting system, such as Maerospace’s ADVISOR service, the analysts can focus their time and effort on the core problem they are trying to solve.
Only humans can set goals and make important decisions to deploy assets. Using AIS and S-AIS data can aid in those decisions, but only if the underlying truth of the data is understood correctly. Using analytic support tools such as TimeCaster™ can enable faster as well as better decisions.
In our next entry in this series, we will explore how AIS and S-AIS data are deliberately or inadvertently misused to hide ships and ship behavior from those who rely on AIS and S-AIS data.
About Maerospace Corporation
Maerospace Corporation, based in Canada, is a global supplier of real-time, predictive analytics to the maritime market. Their core product, TimeCaster™ provides a dramatic improvement in the accuracy and completeness of the maritime picture. Our Advisor™ product analyzes this information to detect and provide real-time alerts on anomalous behavior. TimeCaster™ and Advisor™ together deliver the world’s most accurate picture of the maritime domain for maritime authorities internationally as well as for commercial ship and cargo tracking companies. For more information, visit www.maerospace.com or email us at email@example.com.
cloudeo operates a unique, vendor-independent, data-agnostic market platform through which customers can obtain professional geoinformation services from leading national and international providers at low cost. Services include dedicated solutions for many industries; such as agriculture, urban and landscape planning, logistics, telecommunications, and water management. Customers are provided with high-resolution imagery, 3D terrain models, thematic maps, and sensor data for a wide range of applications. The TimeCaster™ service in our cloudeo web application is available on
TimeCaster™ is a significant step up from standard S-AIS data, using big data analysis for near real-time tracking that is ten times more accurate. Follow the link to subscribe for AIS