How does GPS work?

Of course, as a Nautical Specialist, I also deal with the international discussion on the advantages and disadvantages of satellite-based navigation, e-navigation and conventional terrestrial and astronomical navigation.

In my announced sequel, the second part of GPS, it is primarily about the technical and physical operational and functional limitations to which GPS is subject. These limitations, in part, have serious implications for the accuracy of GPS, and even go as far as limiting the functionality of GPS in its functions or even making it impossible. In doing so,

The vulnerability of GNSS in shore-based use is definitely different and to be regarded as much more risky than on the high seas.

At sea, space technology is used to help save lives every day: managing traffic between ships, picking up migrants and refugees in distress or spotting oil spills. The European Space Agency is once again at the forefront developing new technologies and satellites: to keep us safe at sea and to monitor the environment. Space makes a difference here on Earth and certainly at sea where there is no infrastructure.
Recommendation by Marine-Pilots.com
AIS services are offered by, for example:

Online survey among maritime pilots in Germany: job-related stress and strain and the effects on their work ability.

by Rhys Davies, current Apprentice. Published already in Feb. 2020 by ABP.

Maritime pilots work in an irregular deployment system (rotation system) with unpredictable work assignments under high levels of physical and mental stress. Fatigue or chronic diseases, e.g. coronary heart disease, peptic ulcers or gastritis can occur as a consequence.

Another great education video by Knud Benedict (Germany): Practical experiments for getting useful data for planning.

GNSS interference has become a growing challenge in the Baltic Sea, affecting maritime navigation, aviation, and critical infrastructure. While numerous datasets and services, such as gpsjam.org, spoofing.skai-data-services.com, and flightradar24, report high-altitude GNSS interference based on ADS-B data, there is a significant lack of studies focusing on ground-level interference.