Weekly AIS shipping density.
Monthly AIS shipping density.
UK AIS coverage is neither complete or continuous. There are gaps in the coverage and not all areas are covered 24 hours a day.
The maps on the right shows a summary of AIS coverage over the last rolling week or last rolling month. Darker area have better AIS coverage (and more ships). Gaps in the coverage may be because there are no suitable receivers in the area or because the ships are too far from the coast.
The colours represent the ship type:
red = tanker, blue = passenger and cargo, green = other (eg trawlers, tugs).