Ship speed reduction lowered coastal air pollution


Environmental benefits also included less risk to whales and ocean noise


Blue Whales(VENTURA, Calif. — April 4, 2024) Results from the 2023 Protecting Blue Whales and Blue Skies vessel speed reduction (VSR) program show it reduced coastal California air pollution, risk to whales and ocean noise.

Participating companies reduced ship speeds off California, transiting at 10 knots or less in the San Francisco and Monterey Bay region and the Southern California region, including Ventura County. The voluntary incentive-based program ran from May 1 through December 15 with 33 global shipping companies participating.

Results showed:

● Participants reduced their air pollutant emissions by approximately 1,250 tons of nitrogen oxides (NOx) and 45,000 metric tons of regional greenhouse gases (GHG). This is a 27% reduction in NOx and GHG pollution from the participating ships compared to 2016 baseline conditions. The NOx reductions are equivalent to converting 800,000 passenger vehicles to zero emissions for a single year.

● The transits of participating vessels posed about 58% less of a strike mortality risk to whales than if those vessels did not reduce their speed.

● Ships in the qualifying performance tiers — with 35% or more of fleet total distance in VSR zones traveled at 10 knots or less — had sound levels that were 5.4 decibels per transit lower when compared to 2016 baseline source levels. With a reduction in noise pollution, whales can likely communicate easier.

● Ships in the program transiting the 200-nautical-mile VSR zone in Southern California traveled at 10 knots or less for 83% of the total miles traveled. Cooperation has steadily increased season after season, with about 21% of the miles traveled in 2017 at 10 knots or less.

Automatic Identification System transponders on each ship transmit speed and location. Data was analyzed for each fleet.

Although 2023 was the first year that Protecting Blue Whales and Blue Skies did not provide financial incentives, participation and cooperation levels were the highest since the program’s inception in 2014.

Container, car carrier, bulk and fuel carrier ships are eligible to participate. The program complements the National Oceanic and Atmospheric Administration (NOAA), U.S. Coast Guard and Environmental Protection Agency voluntary requests for all vessels 300 gross tons or larger to reduce speeds during the months of peak air pollution and endangered blue, humpback and fin whale abundance.

Ship strikes are a major threat to whales globally and to the recovery of endangered whales in California waters. Reducing the risk of ship strikes is a high priority for NOAA’s West Coast national marine sanctuaries. Observed and documented deaths off California totaled 52 endangered whales from 2007 to 2022. This is thought to represent only a small fraction of the total number of ship strikes taking place annually.

The timing of the program coincides with the season when ground-level ozone, or smog, concentrations are typically high. The 10-knot target allows ships to travel safely and at an efficient operating load using less fuel and producing less pollution and regional greenhouse gas emissions.

Protecting Blue Whales and Blue Skies is a collaborative effort by the Ventura County Air Pollution Control District and several other air districts, national marine sanctuaries in California, the California Marine Sanctuary Foundation and other nonprofit organizations.

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