What system is primarily used for maintaining accurate tracklines?

The Global Positioning System (GPS) is primarily used for maintaining accurate tracklines due to its capability of providing precise location data in real-time. By utilizing a network of satellites, GPS allows vessels to determine their exact position, speed, and direction. This information is essential for navigation and ensures that vessels can accurately follow predetermined routes, avoid hazards, and implement efficient route planning.

In the context of maritime operations, the accuracy of tracklines directly relies on GPS technology, which is crucial for safe and effective navigation on the water. Other systems like the Environmental Monitoring System or Historical Voyage Recording System may provide valuable data but do not have the same direct application for real-time navigation and accurate positioning that GPS offers. The Marine Traffic Management System may help in monitoring traffic and managing marine operations but it also relies heavily on data provided by GPS for trackline accuracy.