As shipping traffic continues to increase, there is growing concern about the impacts this may have on the marine environment ranging from species-level to ecosystem services.
Commercial shipping uses low-cost heavy fuel emitting significant amounts of sulphur, nitrogen, metals, organic compounds and aerosols to the atmosphere during combustion (Eyring et al. 2005). As most of these compounds have a limited residence time in the atmosphere they are deposited relatively close to the source and dissolve in the surface ocean. Several abatement techniques exist for achieving the required emission limits included in MARPOL Annex VI and EU Sulphur Directive EU 2012/35 such as novel engine technologies, exhaust gas recirculation or fuel emulsifiers etc. Open-loop exhaust gas cleaning systems (‘scrubbers’) belong to the commonly used and cheaper technologies (as alternative to expensive low-sulphur fuel for shipping companies) but are ecologically questionable
