Cruise liners: lucrative but poisoning business

Cruise ships often berthing in harbours in close proximity to dense urban areas such as the Grand Harbour contribute massively to air pollution that threatens climate, environment and human health

Shipping adds on to Malta’s significant air pollution caused by traffic, energy generation and industry
Shipping adds on to Malta’s significant air pollution caused by traffic, energy generation and industry

Shipping, including the lucrative cruise liner industry, is one of the major causes of pollution in Malta, a recent study confirmed. 

The giant ships and thousands of tourists swarming out of them has become an every day sight in Valletta, but there is more to it than meets the eye. 

A measuring exercise carried out in December 2016 in Valletta and Birgu by a number of organisations, including BirdLife Malta, showed that concentrations of ultrafine particles in the ambient air during the time ships were transiting are 80 times higher than clean air levels expected of areas not exposed to any pollution sources.

According to the National Statistics Office, shipping creates 15% of Malta’s Greenhouse Gas emissions caused by the transport sector, which itself is the major contributor with over 90% of Malta’s emissions coming from vehicles, ships and aircraft. 

Scientific data on the extent of air pollution caused by ships in Malta is not currently available, chiefly due to a lack of awareness on air pollution caused by ship traffic. 

The cruise liner industry is often lauded as one of the key pillars in the tourism sector. Cruise shipping movements in Malta have steadily increased over the past few years with 316 ships berthing in the Grand Harbour in 2016. In the same year, cruise ship passengers stood at 626,082, a rise of 4.3% in comparison to 2015.

In Malta, data measured by the air quality monitoring stations are not able to distinguish between emissions from ships and other sources and the monitoring station in Kordin, which is closest to the Grand Harbour no longer measures data. 

A member of the project team told MaltaToday that “because of Malta’s small size, it can be assumed that a major part of the island is affected by the above-mentioned impacts.”

Janina Laurant said this adds on to Malta’s significant air pollution caused by traffic, energy generation and industry, identified as major concerns to the environment and health under the Strategic Plan for Environment and Development (SPED). 

Laurant told MaltaToday that air measurements from monitoring stations should be carried out at suitable locations as per air quality standards under the EU. “For Malta, we would recommended to install a monitoring station at a strategic location near to the Port of Valletta. With suitable equipment, this would assist in gaining scientific data of air pollution caused by marine traffic in the area,” she said. 

Running engines of ships contribute considerably to global and local emissions of sulphur oxides (SOx), nitrogen oxides (NOₓ) and particulate matter (PM). The latter includes soot emissions (black carbon) which are in particular harmful to health and climate.

During a typical 10-hour stay in a harbour, one single cruise liner produces about 66 tonnes of CO2, the equivalent of what 6 Hummers produce in a year. 

Nitrogen oxide emissions diminish the function of the lungs and increase the risk of cardiovascular disease. Nitrogen oxide is also a powerful greenhouse gas causing climate warming due to its contribution in the formation of ozone. High concentrations of ozone in cities is responsible for the death of elderly people and people with poor health conditions.

Emissions of sulphur oxides such as sulphur dioxide are harmful for our environment, not least because it causes acid rain which leads to the eutrophication of soils and coastal areas and it damages buildings and structures, particularly those made of limestone. Air pollutant emissions are furthermore responsible for a significant loss of productivity in agriculture and have a negative impact on biodiversity.

Transport kills 

According to SPED, Malta’s Greenhouse Gas emissions increased by 54% between 1990 and 2012, the transport sector being the principal contributor with 91.1% in 2012.

In terms of CO2, emissions from cars, ships and airplanes have cumulatively increased by approximately 16.3% from 2005 levels.

The bulk of Greenhouse Gas emissions are the result of fuel combustion from road transportation, which amounted to approximately 83.9% of the transportation sector in 2014. This was followed by emissions from domestic navigation, at 15.4% of total transportation emissions and from national aviation, at only 0.6% of total transportation emissions. 

In terms of the type of greenhouse gas, CO2 comprises by far the largest share, with 98% of emissions from fuel combustion in the transportation sector. This is followed by nitrous oxide (N20) at 1.7% and methane at 0.3%. Since 1990, GHG emissions from transport (in CO2 equivalent), have increased by 89.9%.

In 2012, the World Health Organization identified that 95% of Europeans living in urban environments are exposed to levels of air pollution considered dangerous to human health and about 420,000 premature deaths are known as a result in the European Union.


Asked whether the emissions can be controlled, Laurant said “yes, they can,” adding that a number of measures for the shipping sector already exist. 

“In the scope of our project, we are aiming to identifying together with national stakeholders those which are most suitable for Malta,” she said. 

Among these are political measures such as the reduction of sulphur dioxide and nitrogen dioxide emissions by establishing so-called emission control areas (ECAs) and the creation of national tailor-made policy frameworks, such as Emission Control in Malta’s national waters.

Additionally technical measures can be implemented, such as the installation of diesel particulate filters (DPF) on all cruise and ferry ships berthing in Malta, which reduce soot emissions almost completely.

Laurant also recommends the use of selective catalytic reduction systems (SCRs) which eliminate most of the nitrogen oxides from ships exhaust fumes and promoting the use of Liquefied Natural Gas (LNG) which reduces the emissions of sulphur dioxide and PM emissions by up to 99% and of nitrogen oxides by up to 80% for some ships, however, the positive balance in terms of air pollution can be counteracted by escaping methane which is even more harmful then air pollution from the usage of heavy fuel oil.

She also said that emissions can be reduced through ecological port fees which would see ships pay their port fees depending on their environmental performance, including their respective emission balance.

“These should motivate ship operators to invest more quickly in clean technologies,” Laurant said. 

She added that incentivising cleaner shipping could also lead to bigger use of sea transport in Malta which in turn will reduce pollution caused by cars.