How bad is cruising for our environment?


Mainstream media is increasingly reporting on the negative environmental impacts of cruising

On Sunday Royal Caribbean’s Harmony of the Seas sailed from Southampton, the largest cruise ship ever built with 16 decks, 5,479 passengers and 2,300 crew, a population the size of St Ives, Thirsk or Lutterworth, and with seven distinct neighbourhoods. Harmony of the Seas will operate out of Barcelona and Fort Lauderdale. Cruise Lines International Association forecasts 24 million cruise passengers in 2016 up from 15m in 2006 and 1.4m in 1980. Click here for more information.

Harmony of the Seas is reported to be 20 percent more fuel efficient than its sister ships due to a combination of new scrubber technologies, a redesigned hull and a unique “bubble system” allowing it to glide more smoothly through the waves. Of course, the international cruise liners, as with international aviation, escaped Kyoto and the Paris Agreement in December last year. The International Maritime Organisation reports that maritime transport emissions, of which the cruise lines are part, is responsible for between 2.4 and 2.6% of global greenhouse gas emissions which may sound a small amount but if marine transport was a country it would be in the top 20 emitters.

There has been some coverage in the mainstream media of the pollution caused by cruise ships. The UK’s Daily Mail carried a critical story this week: “Massive cruise liners ‘each spew out as much sulphurous emissions gas per day as 376 MILLION cars’ it is revealed as experts call for action on the pollution they cause in port cities”. The Guardian headlined its story “The world’s largest cruise ship and its supersized pollution problem.” They quoted Cruise Lines International Association (CLIA) about investments in new technologies to reduce air emissions but there is increasing criticism of the environmental performance of the cruise industry as academic work finds an audience through the mainstream press. The Guardian has a dramatic graphic revealing the scale of the emissions and quoting Daniel Rieger of the German environment group Nabu.

“Cruise companies create a picture of being a bright, clean and environmentally friendly tourism sector. But the opposite is true. One cruise ship emits as many air pollutants as five million cars going the same distance because these ships use heavy fuel that on land would have to be disposed of as hazardous waste.”

Rieger points out that the heavy fuel oil burnt in ships contains 3,500 times the sulphur that the diesel used for land travel.

Noxious emissions and air pollution near airports is major problem but pollution around marine ports is also an issue. In London and Southampton air pollution caused by marine transport is a major issue and there is evidence that it damages residents’ health.  Harmony of the Seas has two four-storey high 16-cylinder Wärtsilä engines which would, at full power, each burn 1,377 US gallons of fuel an hour, or about 66,000 gallons a day.

Cruise lines were working with Friends of the Earth on an Annual Report Card designed to enable consumers to make more informed decisions – the last of these was published in 2014. Subsequently CLIA stopped co-operating with Friends of the Earth claiming that their report card “does not advance the public’s understanding in a meaningful or objective manner.” Without the report card it is very difficult for consumers to make informed decisions about which cruise lines or ships to sail on. Research led by Dr Xavier Font at Leeds Beckett University reported as recently as 2014 that the cruise lines “fail to report on actual performance data on many key environmental and socio-economic indicators.” Jim Walker’s Cruise Law News carries details of continuing damage to coral reefs and the dumping of waste at sea.

There is a great deal that could be done to reduce greenhouse gas and noxious emissions by cruise liners. The  German  Nature  and  Biodiversity  Conservation  Union  (NABU) published a working paper on Clean Air in Ports funded by the EU-Commission – it lists a long lists of things which could be done now with known technology. By 2014 Thomson Cruises, operating older ships, had reduced absolute CO2 emissions by 5% against a 2011 baseline year. Thomson Cruises had reduced per passenger CO2 by 24% since 2007, from 142kg of CO2 per passenger night to an industry-leading 108kg by replacing cruise ships with more efficient models, saving energy on board and changes to itineraries.

“In order to cut fuel consumption – and hence greenhouse gas emissions and air pollutants – TUI Cruises has optimised voyages continually and improved intelligent route planning. Furthermore, silicone anti-fouling paint has been applied to the hulls of all its vessels. This enhances flow dynamics, as do the ducktails installed on the aft ship. Advanced exhaust gas purification and selective catalytic reduction work together to cut sulphur emissions by up to 99% and particle emissions by 60%. The catalyst reduces nitrogen oxide emissions by 75%.” Click here to read more.

Consumer pressure is not likely to go away but neither is it likely to be sufficient to achieve change on the scale needed. Ports can do something to reduce emissions when ships are berthed but the cruise lines resist because it is cheaper to generate power on board rather than to use and pay for shore power. The problem is that ships at sea are regulated by their flag ports and they have little or no reason to address the issue.

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