Sulphate SO4
Sources
Sulphate is released into the atmosphere through combustion processes. The burning of sulphur-containing fossil fuels such as heavy fuel oil or marine diesel oil releases sulphur oxides (e.g. SO2). In the atmospheric reaction with water sulphuric acid is formed.
Health effects
High air pollution through fine particulate matter such as particulate sulphate is responsible for a number of diseases like stroke, heart disease, lung cancer, and both chronic and acute respiratory diseases, including asthma.
Environmental impacts
Sulphuric acid is accountable for 2/3 of the acidification of rainfall. If the acid is washed out of the atmosphere, the acid rain has huge impacts on the environment. It harms soil and is the cause for forest dieback, but also forwards the alteration at buildings.
SO4 concentrations
The concentration of SO4 is higher during winter. Especially in Eastern Europe the concentration reaches 4 µg/m3.
Relative contribution of ships to SO4 concentrations
The relative contribution of ships is slightly higher in the summer months, which is mainly due to overall lower SO4 concentration during the warmer season. The contribution of ships to the concentrations is not so much bound to the shipping routes compared to the SO2 pattern, as the SO4 particles are transported over a higher distance.
Scenario No ECA: SO4 Concentration Change
In the scenarios for 2030 all ships follow the same rules for sulphur, which allow only 0.1% S in fuels within the ECA and 0.5% outside the borders of the ECA. Therefore the scenarios do not differ much in term of sulfur concentrations.
Scenario ECA SCR 21: SO4 Concentration Change
In the scenarios for 2030 all ships follow the same rules for sulphur, which allow only 0.1% S in fuels within the ECA and 0.5% outside the borders of the ECA. Therefore, the scenarios do not differ much in terms of sulfur concentrations.
Scenario ECA SCR/LNG 16: SO4 Concentration Change
In the scenarios for 2030 all ships follow the same rules for sulphur, which allow only 0.1% S in fuels within the ECA and 0.5% outside the borders of the ECA. Therefore, the scenarios do not differ much in terms of sulfur concentrations.
LNG does not contain any sulphur, which is why a difference can be seen between the ECA LNG and the ECA SCR (0.1% sulphur). The ECA LNG 16 scenario shows that SO4 is even further reduced compared to the reduction of the concentration in the ECA SCR 16 scenario. In comparison to the concentration of SO2, the reduction is more widespread.
Scenario ECA opt: SO4 Concentration change
In the scenarios for 2030 all ships follow the same rules for sulphur, which allow only 0.1% S in fuels within the ECA and 0.5% outside the borders of the ECA. Therefore, the scenarios do not differ much in terms of sulfur concentrations.