Duncan Campbell, Solis Singapore, discusses our recent use of heat maps for displaying large volumes of AIS data.
Recently, Solis Marine have increasingly been creating heatmaps from large volumes of vessel position data as a great way to give a visual insight into vessel traffic flows for various applications. This has been followed up with statistical analysis of data to give further insights into vessel movements and filter the data for various vessel parameters including size, speed, course and AIS vessel type.
The example screenshots shows a heatmap produced from three days of AIS data of all vessels above 150 metres in length for the port of Shanghai.
Figure 1 3 days of traffic in Shanghai (vessels >150m)
There are a wide range of applications for the use of these heatmaps and the associated statistical analysis.
A vessel route can be analysed and compared to other vessels of the same type and size travelling along the same route to see if the grounded vessel took a substantially different route to what is expected and taken by other vessels.
Berth Damage Claims
For checking the usage of a berth after an incident and verification of claims regarding loss of use or size restrictions on ships using the berth. Berth usage before and after the incident can be analysed and statistics given for how many ships are using the berth per day/week/month. A heatmap is generated to visually show the differences in berth usage for various types and sizes of vessels.
Figure 2 6 months of traffic at St Eustatius
With wash damage claims it is often useful to understand if the traffic passing a moored vessel was travelling at excessive speed or closer to the berth compared with other vessels transiting the area.
Heatmaps are a great way to visualise large amount of data when carrying out causation analysis. This is particularly useful when looking at routes taken by vessels and assessing whether manoeuvres that have been carried out are typical for a particular port.
Traffic Analysis for Salvage and Wreck Removal
For salvage and wreck removal projects in areas of high traffic density it is very important to have a full understanding of the actual traffic numbers, density and flow around the casualty site. With this data the risk to the project posed by other vessels in the vicinity can be quantified and appropriate risk reducing measures can be put in place to help mitigate the risk.
There are numerous other applications for heatmaps and the associated statistical analysis, please contact Duncan Campbell (firstname.lastname@example.org) for more information.