emissions reduction

GeoSciences Column: The dirty business of shipping goods by sea

“Above the foggy strip, this white arch was shining, covering one third of the visible sky in the direction of the ship's bow,” he explains. “It was a so-called white, or fog rainbow, which appears on the fog droplets, which are much smaller then rain droplets and cause different optic effects, which is a reason of its white colour.”

Shipping goods across the oceans is cost-effective and super-efficient; that’s why over 80% of world trade is carried by sea (according to the International Maritime Organisation). But the shipping industry also contributes significant amounts of air pollutants to marine and coastal environments.

A new study, published in the EGU’s open access journal Earth System Dynamics, reports on concentrations of sulphur, nitrogen, and particulate matter (PM), from 2011 to 2013, in the Baltic and North Seas – one of the busiest shipping routes in the world. The study aims to provide policy-makers with better knowledge about how shipping impacts local environments. The end-goal being better industry regulations and technology to make shipping more sustainable in the long-term.

The reality of shipping goods by sea

In the past two decades reduction pledges, like the Paris Climate Accord, and strict regulation have driven down air pollutants from land-based emissions across Europe, but greenhouse-gas emissions from the shipping industry are not subject to as strict international protocols.

And that’s a problem.

It is estimated that there are about half a million ships in operation at present, which together produce almost one billion tonnes of carbon dioxide each year (that’s more than Germany emits in the same period!). Over the past 20 years, emissions of pollutants from shipping in the Baltic Sea and North Sea have increased.

Worryingly, economic growth in the region means shipping is only set to increase in the future. In fact, the European Commission predicts that shipping emissions will increase between 50% and 250% by 2050.

Why should you care?

While cruising the high seas, ships emit a dangerous cocktail of pollutants. When burnt, their fuels emit sulphur dioxide and as ship engines operate under high pressure and temperature, they also release nitrogen oxides. Combined, they are also the source of particulate matter of varying sizes, made up of a mixture of sulphate (SO4), soot, metals and other compounds.

The authors of the Earth System Dynamics paper, led by Björn Clareman of the Department of Earth Sciences at Uppsala University, found that international shipping in the Baltic Sea and the North Sea was responsible for up to 80% of near-surface concentrations of nitric oxide, nitrogen dioxide and sulphur dioxide in 2013.

Total emissions of SOx and deposition of OXS (oxidized sulphur) from international shipping in the Baltic Sea and North Sea in 2011. From B.Claremar et al., 2017.

In addition, the team’s simulations show that PM from shipping was distributed over large areas at sea and over land, where many people will be exposed to their harmful effects. The highest concentrations are found along busy shipping lanes and big ports. In total, shipping was responsible for 20% of small sized PM (known as PM2.5) and 13% of larger particles (PM10) during the studied period.

These pollutants have harmful effects on human health: It is thought that living close to the main shipping lanes in the Baltic Sea can shorten life expectancy by 0.1 to 0.2 years. Sulphur oxides in particular, cause irritation of the respiratory system, lungs and eyes; while a 2007 study estimated that PM emissions related to the shipping industry cause 60,000 deaths annually across the globe.

Environmentally, the effects of shipping pollution are concerning too. Deposition of nitrate and sulphate causes the acidification of soils and waters. The brackish waters of the Baltic Sea make them highly susceptible to acidification, threatening diverse and precious marine ecosystems.

The current problem

Legislating (and then monitoring and enforcing) to limit the negative impact of shipping emissions is tricky given the cross-border nature of the industry. For instance, currently, there is no international regulation for the emission of PM. However, the International Maritime Organisation’s (as well as others; see Claremar, B., et al., 2017 for details of all regulations) does impose limits on sulphur and nitrogen emissions from ships (in some parts of the world).

Low-sulphur fuels and switching to natural gas are an effective way to control emissions. However, operators can also choose to fit their vessels with an exhaust gas treatment plant, or scrubber, which uses sea water to remove sulphur oxides – the by-products of high-sulphur fuels. So called open-loop scrubbers release the dirty exhaust water back into the ocean once the tank is cleaned. The practice is known to increase ocean acidification globally, but particularly along shipping lanes.

As of 2021, the transport of goods via the North and Baltic Seas will be subject to the control of nitrogen and sulphur emissions, which could decrease nitrogen oxide emissions by up to 80%. However, the study highlights that the continued use of scrubber technology will significantly offset the benefits of the new legislation. If cleaner alternatives are not implemented, total deposition of these harmful particles may reach similar levels to those measured during the 1970s to 1990s, when shipping emissions were largely unregulated.

By Laura Roberts Artal, EGU Communications Officer


Those who have an interest in this subject might want to contribute an EU Public consultation on the revision of the policy on monitoring, reporting and verification of CO2 emissions from maritime transport. The International Maritime Organisation (IMO) adopted the legal framework for the global data collection system (IMO DCS) in July 2017. This Consultation is now reviewing the situation and would like input on things such as the monitoring of ships’ fuel consumption, transparency of emission data and the administrative burden of the new system. While the Consultation is not specifically aimed toward scientists, it may interest EGU researchers who are working in the marine, climate and atmospheric sciences sectors.


Refences and resources

Claremar, B., Haglund, K., and Rutgersson, A.: Ship emissions and the use of current air cleaning technology: contributions to air pollution and acidification in the Baltic Sea, Earth Syst. Dynam., 8, 901-919,, 2017.

Lower emissions on the high seas. Nature, 551, 5–6, https://doi:10.1038/551005b, 2017

Corbett, J. J., Winebrake, J. J., Green, E. H., Kasibhatla, P.,Eyring, V., and Lauer, A.: Mortality from ship emissions: a global assessment, Environ. Sci. Technol., 41, 8512–8518, 2007.

Dashuan, T., and Shuli, N.: A global analysis of soil acidification caused by nitrogen addition, Environ. Res. Lett., 10, 024019, https://doi:10.1088/1748-9326/10/2/024019, 2015

What is Ocean Acidification? Ocean Facts by NOAA

Reducing emissions from the shipping sector, Climate Action by the European Commission

The energy self-sufficient village of Feldheim – a pioneer within Germany’s energy transition

The Emerging Leaders in Environmental and Energy Policy (ELEEP) Network brings together young professionals from Europe and North America with the aim of fostering transatlantic relations. Former EGU Science Communications Fellow and ELEEP member Edvard Glücksman reports back from a recent study tour, where participants were shown first-hand how a rural German community has successfully achieved a break from the national energy grid and pledged its future to renewables.

Renewables are set to play a vital role within the global energy portfolio of a low-carbon future. In parallel with this year’s UN climate change conference in Warsaw (COP19), which, earlier this month, proceeded cautiously and not without controversy, we explored a series of German prototype community projects built to demonstrate that modern life is indeed possible under conditions of minimal fossil fuel consumption, albeit on a local scale.

We visited a house in Berlin capable of producing an energy surplus and a district of Hamburg made up entirely of eco-friendly housing prototypes. Yet, in my opinion, our most impressive visit was to the remote village of Feldheim (with a population of 128 people), located in the district of Treuenbrietzen, about 80 km southwest of Berlin.

On the spectrum of climate-friendly projects, Feldheim represents an extreme outlier as a microcosm showcase of a zero-emissions future: it is Germany’s first and only energy self-sufficient community, a pioneering working example of economically beneficial renewable use.

: ELEEP members visit Feldheim’s extensive wind farm, a major component in the community’s energy self-sufficient existence. (Credit: Edvard Glücksman)

ELEEP members visit Feldheim’s extensive wind farm, a major component in the community’s energy self-sufficient existence. (Credit: Edvard Glücksman)

The Feldheim project dates back to 1995, when a local entrepreneur paid for the first wind turbines to be installed on nearby fields, the highest (and windiest) flat ground in the state of Brandenburg. Next, the village bought its own electricity grid, severing ties with the regional grid and the major national provider that operates it. This vital transition required a steep initial investment of €2.2 million, financed through one-off connection fees paid by local homeowners together with subsidies of €850,000 provided by the German government and European Union. Finally, the village forged links both with local power firm Energiequelle GmbH, which agreed to install a fleet of wind turbines in return for the right to sell excess power back on the market, and with a regional agricultural cooperative, which put up over 350 hectares of land to grow corn required for biogas.

A profitable three-pronged approach

Feldheim derives its electricity and heating from three main sources. Firstly, a 43-turbine wind farm, with a total installed electrical capacity of 74.1 MW, generates 129 million kWh of electricity per year, or enough to power nearly 7,000 UK homes. Simultaneously, a biogas plant (500 kW), operated by the local agricultural cooperative, generates 4 million kWh of electricity per year (enough to power just over 200 UK homes) from an input of manure, corn, and whole grain cereal. Electricity from the biogas plant is sold on the public market, but the heat produced during power generation is fed into a separately-installed heating grid, which heats the village’s private homes, commercial enterprises, and livestock enclosures. Finally, on particularly cold days, additional heating is supplied through a 400 kW woodchip furnace, though we were assured that its prolonged use is relatively rare and that all wood is collected locally and in a sustainable manner (using branches only).

Feldheim derives its energy and income from a mixed portfolio of renewables. (Credit: Edvard Glücksman)

Feldheim derives its energy and income from a mixed portfolio of renewables. (Credit: Edvard Glücksman)

This three-pronged approach affords Feldheim an existence free of fossil fuels, something its inhabitants are visibly proud of. However, perhaps more important from a global perspective, and certainly what has raised most eyebrows in Germany and internationally, is that the project clearly demonstrates that renewable energy investments can have tangible long-term economic benefits.

Feldheim consumes under 1% of the electricity produced annually by its wind turbines, selling the remainder back on the market; the process lowers local electricity bills to around half (16.6 cents per kWh) of the national average and to around the same level as in Poland, where over 90% of electricity is generated using carbon-intensive coal-fired plants. At the same time, also selling its electricity back to the market as well as supplying the entire community with heating, the village’s biogas plant saves the inhabitants of Feldheim over 160,000 litres of heating oil each year. It is set to break even on the initial investment of €1.75 million towards the building of the plant within a decade.

Spearheading the energy transition

Having understood the economic potential of renewables, Feldheim took yet another pioneering step when, in 2008, it constructed a solar farm comprising 284 panels. The installation produces a total annual output of 2,748 mWh, or enough to cover the annual power requirements of around 600 four-person households. The construction of the panels, which sit on trackers that tilt horizontally and vertically, has also created 20 local jobs and rejuvenated the 45-hectare area of Selterhof, a former Soviet telecommunications centre dismantled and restored to its natural state as a result of the project.

Energy generated by way of photovoltaics is sold back to the market, subsidising the cost of electricity for Feldheim residents. (Credit: Edvard Glücksman)

Solar energy is sold back to the market, subsidising the cost of electricity for Feldheim residents. (Credit: Edvard Glücksman)

Understandably, the small population of Feldheim is optimistic about the nation’s renewable energy future and their enthusiasm seems to be catching on. In the cash-strapped state of Brandenburg, where other villages suffer 30% or higher unemployment rates, every single resident of Feldheim is employed, mostly working at one of the renewables sites.

The community continues to plan for the future, the next step being the installation of a lithium storage battery by the end of 2014. The battery will provide enough electricity to supply the village for up to four days, in the unlikely scenario that wind levels drop for a sustained period of time.

Yet, Feldheim remains just a small piece in the wider context of Germany’s energy transition (‘Energiewende’), announced in June 2011 by Chancellor Angela Merkel’s government. In doing so, Merkel set the country on an incremental course to generate 80% of its power through renewable sources by 2050 at an estimated cost of €550 billion. At the same time, the EU’s most populous Member State, home to over 80 million people, continues to reduce its reliance on nuclear power, aiming to phase it out completely by 2022.

COP19 protagonists Lord Stern and Christiana Figueres increasingly push their sense of urgency whilst negotiators continue to grapple with the mission of reaching a new international climate change agreement by 2015. Meanwhile, many of the planet’s most powerful nations struggle to see clearly how economic growth by way of fossil fuel consumption can be reconciled with climate concerns. Perhaps, then, the village of Feldheim and its 40 residential homes, church, community centre, and lack of shops and pubs, can serve as a beacon through the smog.

By Edvard Glücksman, Postdoctoral Research Fellow, University of Duisburg-Essen

ELEEP is a collaborative venture between two non-partisan think tanks, the Atlantic Council and Ecologic Institute, seeking to develop innovative transatlantic policy partnerships. Funding was initially acquired from the European Union’s I-CITE Project and subsequently from the European Union and the Robert Bosch Stiftung. ELEEP has no policy agenda and no political affiliation.