Cruise ships pumping more harmful gases in Europe

Cruise ships pumped four times more harmful sulphuric gases into the atmosphere in Europe than passenger vehicles last year, according to new research showing air quality is deteriorating despite emissions limits and industry pledges to go green.

A total of 509 tonnes of sulphur oxides were emitted by the 218 cruise vessels in operation across Europe last year, up from 465 tonnes of emissions linked to the industry in 2019, the last year of normal activity before the pandemic, according to a report by climate lobby group Transport & Environment.

A 0.5 per cent cap on sulphur content in marine fuels introduced in 2020 by the International Maritime Organization has helped to cut sulphur emissions per tonne of fuel consumed. But dozens of extra cruise ships have been added to the main operators’ fleets since 2019, which has increased total emissions. This is despite passenger volumes in Europe not yet rebounding to pre-pandemic levels.

Sulphur oxides have been proven to cause acid rain and can aggravate respiratory conditions such as asthma and emphysema. Barcelona ranks as the worst-affected port city in Europe for sulphur emissions, with a total of 805 port calls by cruise ships leading to 18 tonnes of sulphur oxides being released into the atmosphere last year.

The research also showed that since 2019 emissions of nitrous oxides and PM2.5 particulate matter, which are both linked to respiratory diseases and lung cancer, had increased by 18 per cent and 25 per cent respectively.

Although cruise ships account for a fraction of the emissions linked to the wider global shipping industry, the sector has come under fire from regulators, politicians and activists who are pushing for it to clean up its environmental record.

A host of European port cities, including Palma de Mallorca, Marseille, Dubrovnik and Santorini, have placed restrictions on the industry in recent years. Most notably, Venice banned cruise ships weighing more than 25,000 tonnes from its lagoon to protect its Unesco world heritage site status in 2021. Emissions of sulphur oxides fell by 80 per cent in Venice as a result, according to the research.

In Barcelona, the outgoing leftwing mayor Ada Colau has led a crusade against cruise ships and urged the Catalan regional government to restrict the number allowed in its port. All the contenders to replace her — who are haggling over potential governing coalitions after an election last month — agree that cruise tourism must be reformed to do the city less harm.

Carnival, the world’s biggest cruise operator, had the highest sulphur emissions of any operator, with its fleet of 63 ships emitting 43 per cent more sulphur oxides than all of Europe’s passenger vehicles.

The Florida-headquartered company was fined $20mn in 2019 by US prosecutors over environmental violations. It said it was the only major cruise company to reduce its greenhouse gas emissions since 2011 despite increasing its fleet capacity by 30 per cent.

The IMO’s sulphur cap led to an increase in the use of so-called scrubbers, which remove sulphur from the ship’s exhaust by collecting the air pollution and disposing of it at sea — to the detriment of marine life.

Scrubbers were also behind a significant jump in particulate matter emissions from cruise ships, according to Transport & Environment, which has called for a ban on the cleaning system in certain ports to be extended to all European waters.