Fig. 2. Proportion of fleet affected by four noise reduction
strategies
The height of each stacked bar represents the percentage of the fleet
(population of 1,582 ships) that would be affected by four different
strategies for halving the total radiated power. Removal of gross
polluters affects 15%; limiting them to a noise threshold of 175.4 dB
affects 42.8%; enforcing a speed limit of 11.8 knots affects 83%; and
having all ships reduce their source level by 3 dB affects 100%. Colors
indicate the classes of affected ships and the thickness of any colored
bar section depicts the portion of the fleet that has affected ships in
the class associated with the color.