Sustainable shipping and environment of the Baltic Sea


BONUS SHEBA has resulted into significant new information related to the recent development of shipping scenarios and impacts of shipping in the Baltic Sea. In collaboration with other BONUS projects looking at other sectors, scenarios are also being developed for shipping within Shared Socio-Economic Pathways for the region.

First about BONUS SHEBA…
It maps all types of pollution originating from ships and provides an integrated and in-depth analysis of the ecological, economic and social impacts of shipping in the Baltic Sea. It brings together experts from the fields of ship emissions, atmospheric, acoustic and oceanic modelling, atmospheric and marine chemistry, marine ecology, environmental economics, and social sciences to work together in support of the related policies on EU, regional, national and local levels. BONUS SHEBA is a flagship project of the EU Strategy for the Baltic Sea Region and affiliated to the research network Baltic Earth.

Air Pollution:
For assessment of air pollution from shipping, an ensemble of atmospheric chemistry transport models was ran for year 2012 and for several scenarios for year 2040, both for the whole Baltic Sea region and for 4 harbour cities. The model simulations show that today, shipping is the most important source for nitrogen dioxide (NO2) in the atmosphere over the Baltic Sea. On annual average, NO2 concentrations are in the order of 8 ppb in busy shipping lanes, which is typical in smaller cities. Scenarios for 2040 show a significant reduction of the NO2 concentrations in the area, also those stemmed from shipping. This is mainly driven by energy efficiency increases that are projected for ships in the next 20 years as well implementation of a nitrogen emission control area in the North and Baltic Seas in 2021. Ships visiting ports can be responsible for large parts of the NO2 concentrations in respective cities. E.g. in Gothenburg, model simulations show that currently, almost half of the NO2 concentrations in the northern part of the city stem from ship exhaust.

Pollution via water:
Load factors for pollutants from sewage, food waste, bilge water, scrubber water, ballast water, stern tube oil, operational oil discharges and antifouling paints have been produced and a spatio-temporally resolved inventory of pollutants for the entire Baltic Sea has been calculated. As an example, the emission inventory on the load and distribution of shipping-originated copper has shown that >99% of c.a. 300 t copper emitted annually by shipping originates from antifouling paints. Furthermore, the oceanic model shows that the highest concentrations of copper are not always where the shipping lanes are located but near the biggest harbours where ships spend most of their time.

Underwater noise: Commercial shipping is a major source of noise in the sea
Both natural and man-made activities can generate loud noise, which can disturb marine life. Natural sound is occasional and not always present whereas the increase of shipping in the last decades have made man-made sounds constantly encountered in world’s oceans. In recent times, initiatives to achieve a better understanding of underwater noise from shipping has been initiated e.g. by the Commission and the IMO.

The BONUS SHEBA project builds on the experience of previous research efforts in the field of underwater noise and has generated a computer model based estimates of underwater shipping noise. The noise generated by ships’ propellers, propulsion machinery and hull are described with a simple model which uses actual traffic data and performs a vessel-specific noise estimate for the Baltic Sea fleet. The noise source spectra of ships were estimated from long term measurements by hydrophone deployed near a major shipping lane south of the island Öland. The derived source estimates were subsequently used in a noise propagation model to compute maps of the shipping-generated noise in two test areas, illustrating the effect of e.g. traffic density, bathymetry and sound speed variations on the noise level.