Commercial shipping as a source of acidification in the Baltic Sea (SHipH)

Research Project, 2013 – 2016

Sulphur and nitrogen oxides (SOX and NOX) from ship exhausts are a potentially significant contributor to Ocean Acidification in heavily trafficked areas. The maximum sulphur content of marine fuel oil in Emission Control Areas (including the Baltic Sea) will be reduced from 1% to 0.1% in 2015. Two possibilities are available for commercial shipping: to use expensive low-sulphur fuel, or to use seawater scrubbing systems to absorb acidic gases from the engine exhaust. This second option generates large volumes of seawater at pH 3, which acidify the water if not neutralised before release. In either case, the consequences of the release for marine organisms are unknown. This project will examine the consequences for the Baltic Sea of SOX and NOX emissions from shipping. A range of scenarios will be developed by combining current projections from IPCC and EMEP, downscaled to the Baltic, with different options for the use of low-sulphur fuel, or high-sulphur fuel with scrubbing. In addition, the biological consequences of releasing scrubber output will be assessed on natural pelagic communities in different target areas. The scenarios will be developed in dialogue with a reference group representing the shipping industry and government authorities. A monitoring programme for shipping-derived acidification in the Baltic will be designed. The results of this research will support future policy development for regulation and monitoring of SOX and NOX emissions from shipping.