Greenhouse gas emissions caused by operations at the Port of San Diego dropped by 42 percent between 2006 and 2012, according to a report released Wednesday by the agency.
Emissions of other harmful air pollutants were also significantly reduced, including nitrogen oxides by half, diesel particulate matter by 75 percent, and sulfur dioxide by 94 percent, according to the port.
"By reducing greenhouse gas emissions and air pollutants, we have a positive impact on climate change while also improving air quality for local communities," said Bob Nelson, the Port Commission's chairman. "This environmental monitoring shows that our strategies have been effective as we strive for green maritime operations."
According to the port, emissions were measured in 2006 to provide a baseline and were followed by steps to reduce air pollution.
The actions taken to reduce emissions included asking cargo ships to reduce their speed to 12 knots, and cruise ships to 15 knots, while in the bay and 20 miles out to sea from Point Loma.
The port also set pollution standards for trucks that drop off and pick up cargo at the port, and installed pier-side systems that provide power to ships, so they don't have to keep their engines running while tied up.
Port officials also credited state pollution control regulations, the use of cleaner fuels and the recession that took place during the period that was studied.
